Bacne?? No thank you!

I'm 21 and sexually active here and there but I've been off birth control for about a year just by random choice. But I've gotten crazy acne on my back and chest and it's driving me insane! Does anyone have any advice on what to go on to help with it? I seriously think I've been on every pill but never found one that particularly worked for me. My periods tend to be absolutely insane in every aspect. I just want something to help with the acne at this point and I do not want to gain weight. Help?? What pill worked for you?