If you're 4months pregnant use the time to study (since you won't be partying). I was a teenage mother too, it's not easy - actually I'll rephrase that, it's hard as fuck! But you can do it, believe me My eldest is 18 now and we have a great relationship, he's a wonderful kid and he never gave me an ounce of trouble ( my Dad says I got off way too lightly considering the time I gave him and my mother ~lol~)
Anyways, welcome to the board