Could I get pregnant like this? PLEASE HELP?

I'm 17. My boyfriend and I were fooling around. He did not penetrate me, but our respective parts did come in contact with each other more than just a few times. He didn't have a condom on most of the time. Now my period is 12 days late. I got it last on the 20th of March. I haven't taken a pregnancy test yet, but I wanted to know if I could be pregnant. Apparently for some people, you cannot detect it until three or four months after you get pregnant. Is that true? So if I take the test and it's negative, is it possible that I could still be pregnant? Also, I've been getting a white discharge & wetness for the past week. Everytime I think I've got my period, but when I go check, I don't have it. I can't go to a gynecologist 'cause I'm not legal yet! Or I can't take tests from a hospital/clinic cause I need to be 18 for that, if I don't want my parents finding out. PLEASE HELP!