Is my game over?

I play Skyrim on PS3. I am level 71 with my skill constellations all at level 100 (or at least in the high 95+ range). I can't seem to find any main or side quests to complete. All I seem able to do are the Companions quests, Thieves Guild jobs, or Dark Brotherhood contracts...over and over and over again. Is my game over? Please help. I welcome all insights. Thanks.

PS Skyrim rocks!

you could either
-get PC version and mod the game until it is unrecognizable
-roleplay instead of power-leveling like you did haha
-move onto another game and wait for DLC

how many hours did it take you?

Become Thane of all Holds?

Create a new character or go explore random caves if you know you haven't gone into every single one

When I get to the point of every quest is done and all else is "meh" i move on to a new character. I make changes, slow down on quests and role play through it. Since I love building the sneak-archer I find a way to use that aspect in every character. I had fun with my wood elf warrior; archery, 1 and 2 handed and block.

I'd suggest starting a new character, perhaps upping the difficulty. Role play a certain playstyle. I've been playing this game ever since it's release and I still manage to find things to do. O'course I have a ton of different characters.

Thanks to all for your ideas. I guess I will play a new game with a different character and see what happens. Skyrim is a really awesome game. I hope they create a multiplayer Skyrim next.
Yes, I am Thaine of every major city. And I do still stumble across an undiscovered cave or mini quest... like the dead treasure hunter I happened across today while playing, but I have nearly maxed-out this game I think. What Fun!
PS i haven't checked my game play hours...over 250-300 i would think.

Get out there and clear every location in the game, then you've done it all!

I found that making a character you are uncomfortable with adds a whole new feel. So, if you have been a Mage, create a character that doesn’t use Magik at all.

My advice is basically what everyone else here said; create a new character. If you're too uncomfortable with an entirely new character, you could try making your new character look like the old one, but going for the exact same abilities might make it a bit too repetitive. For example, if you were a warrior before, try stretching into magic a bit more. When you create a new character, try doing all the smaller quests before the main storyline or the guild quests, so you save the important stuff for as long as possible. Also try a "Day A Day B" schedule if you want; One day you could explore around Skyrim and 'collect' quests, and the next day try to focus on completing them. Also, look around for quests you haven't done before. Sometimes, it can feel like paying an entirely diffrent game!

Ok. Thank You to everyone who has provided all the useful information. I have been doing what you have asked, more exploring on foot rather than 'Fast Traveling' to the objectives, and I have encountered a host of new Side Quests and unlisted mini quests. - For example: I ran into The Blades again in Sky Haven Temple or Karthspire and this opened up a new set of quests. I forgot all about them...it was soo long ago. I also noted that some quests are not even opened and active to your character until you have reached a prerequisite skill level... like with Kahvozein's Fang (when your Alteration skill reaches level 90). -
Anywho, Skyrim rocks! I'll keep searching and exploring. I hope I hit Two Mil. in gold soon too.
Hey, will every location on my map really say and stay 'Cleared' or will the passing of time 'Un-Clear' a location?
Oh, and also, I checked my game time... 577 hours and going.
Thanks.

Signed,

Patiently waiting for Skyrim II High King Cicero.

Get all Dragon Priest masks. Do all Daedric quests. Find all word walls if you haven't found them already.

After you clear most locations, they have a "respawn" time of 1-15 game days and whoever inhabited them before will be back. Or perhaps bandits will take their place after a certain amount of time.

As for things to do, plenty of what has already been mentioned are great things to do and as you're finding, traveling on foot rather than fast traveling reveals new areas/quests. If you find an unknown location marker on your navigation bar, go check it out and storm through it or leave it be (depending on what your character likes to fight/leave alone).

The phrase "leave no stone unturned" would apply to this situation. Also, when you go through towns, holds, or little villages?, go back and talk to every person you can find there. If you talk to inn keepers, there will be an option of 'do you know of any rumors' or 'I'm looking for work, do you have any leads?' and they should be able to give you a bounty to clear from a Jarl. Normally it's just 'go kill this bandit leader' or 'go kill the giant leader' or something like that. But of course, turning the game up to Master level for a time (if you're not on it already) could prove to be fun too.