I'm 15 and i need to know if i'm pregant

First off I get my period the last week of the month and it ends on the beggining of the next. It ended on the 5 and it's the 28th and i still haven't gotten it. and myy peroid ended I'm really scared, My boyfriend and i had sex and he had troubles putting the condom on but it wasn't broken and he didn't cum in me he pulled out and we cuddled and then he took the condom off and we continued to cuddle. I think his penis was covered in pre cum while we did this the cuddling was face foward so his penis was near my vagina. after wards i gave him oral sex and he came in my mouth not any where else but i think might have gotten some on my hand but i didnt touch myself afterwards. Later on the week we had sex again but he had trouble getting the condom on again and he bairly put it on and then inside of me but we stopped since the condom was bairly on. Before hand he had pre cum and it got on my hand but after the condom didn't work i proceeded into giving him oral sex and then he came in my mouth again and we cuddled naked aggain. After that (might i add that the sex was painful since i wasn't wet the second time and he is fairly large and i'm a small girl) I started to get light brown discharge but then it turned normal and white but then i smoked weed and now my discharge stopped or is very light and crusty. My boobs usually get swollen before my period and i have cold symptoms please help and tell me what i could do.