I feel helpless

To complicate it even more I miss my ex. My daughter was conceived during a "break" in our relationship. I loved him so much but I was under so much stress from school (my pre med people know we're like one straw away from a mental breakdown at anytime). It was a stupid stupid break and it was all my fault. I thought I met someone else. I thought he was my soulmate and now he's my daughters father and I just don't know. I wasn't ready for any of this. I want to go back to no responsibility but I don't want to give up my daughter. I just feel trapped and alone and like I ruined my life. I miss the old me. I feel so helpless. 

I don't think this is at all ppd because it didn't set in until about two months after my daughter was born. And I've been "chemically" depressed before as in I was fine with my life situation but I had some type of imbalance that caused me depression. And this isn't that. I'm upset at the situation and how there's nothing I can ever do to change it. I just wish there was some way to take my daughter and have her in 5 years. Atleast i could've had my career then.