Could I be pregnant?

Hello everyone, I am new to this site. I have a question regarding pregnancy. My Boyfriend and I had unprotected sex in the end of May & in the begining of June, I have always had my period at the same time of the month, well in June I started on the 18th and only for one day. which I usually start on the 24th and last one week! well I then had my period in July which started on the 14th and lasted til the 18th. My boyfriend and I had unprotected sex again on the 19th of July the day after my period stopped. Ever since then I am wondering if I am pregnant. Some symptoms: Head ache, back ache, sometimes feel like I need to throw up, and tenderness in breast. And when I get hungry I feel like I have to eat right the second or I will get sick. I don't know what to do about this and I am very worried about it. I can not sleep at night cause I am thinking about it so much! I have heard that sometimes you can kinda trick your body into thinking your pregnant if it is always on your mind. Also. if I take a home pregnancy test how soon would I be able to tell? It has been 9 days since the last time I had unprotected sex. Unless, I got pregnant in May or June. But what about the period in July? PLEASE HELP ME IF YOUCAN WITH ANY OPINONS OR SUGGESTIONS!!