help! what should i do?

Recently my boyfriend and I learned that i am pregnant, and when i heard that my heart sank. I did not want to have another kid yet, im only 20 and already have a 1 year old. And a few weeks before we found out, I started to become very annoyed with him to the point where anything he did anmoyed me. Now its a month later and I honestly dont feel love for him anymore, and feel like moving on and starting a new life without this new baby, and just my own would be best. i cant stand him anymore, its like i dont want sex, i would rather watcg porn than have sex with him. I feel bad, because he is a great guy, just too many fights about the same thing over and over again, then I get depressed. I have depression and recently i have been more depressed than happy with him. Honestly I just want to not hvae this baby, mive out and live on. I domt know ig this is because Im pregnant, or because I honestly dont love him anymore. Should I wait till the first trimester is over, or shoukd i quit now. Im sorry i just cant live my life like this. He is an amazing guy and would be a great father, but i cant handle staying with someone i dont feel happy with.