Anyway, opening stage: you had a solid position out of the opening with a good spacial plus and a lot of room in the center. Your opponent, meanwhile, had an acceptable position, with no major weaknesses and good chances at attacking your center.
Anyway, I think your first error came on 10: C5, which creates a weak square on D5. I watched the entire game, waiting for black to plant a knight on that square but it never came across. On your next move, you made Bd3, a move I'm not quite certain how to evaluate. While it is true that you traded your "good" bishop for your opponent's "bad" bishop, it also remains true that said bad bishop struck aggressively towards the queenside, and could later pressure your C5 weakness. In addition, it also allows your queen unrestricted access to the light squares, so there are both pros and cons to that move.
Anyway, I think black has an edge after 20... Rd2! and would have had a safe edge had he/she continued 21: RxP! and I'm not quite certain that you have enough counterplay, even with black's doubled pawns.
I'm also not to strong on your 25th move. You essentially give away a pawn, and black should have been able to make you pay for this mistake.
I just got done playing an online 60-minute game, which I won. I was playing White and was rated 1372, and my opponent played Black and was rated 1549. My opponent played the Caro-Kann Defense in response to my 1. e4. It is an opening I have very little experience playing against, and only a dozen or so games worth of experience using it as Black. But, I feel like I did pretty well in this game. There were some mistakes and inaccuracies on both sides (especially when we had come to the endgame), but he made a small miscalculation in the endgame that I pounced on to get the victory. Comments, advice, and feedback welcome.