The usual

So my boyfriend and I have unprotected sex ( we pull out and use spermicide) and this morning I woke up around 4 in the morning and threw up everything I ate that evening and then drank water to keep fluids in my body and threw up that as well in the following two hours. Now i'm not sure if the food I ate was just too acidic and I've been under a lot of stress or if I may be pregnant, I just need reassurance because I have had my PMS symptoms and i'm suppose to get my period today but i give my period an extra week sometimes because it likes to do that often.