Missed period? not pregnant?

so basically i havent had a period since February or March. ive skipped periods before by drastic amounts of time like this but it worries me because I fooled around with a guy. he never came, and my underwear was still on but he did push into me a little (and i am a virgin). but i would think that its highly unlikely that he could have impregnated me that way. I've also been super stressed and worried about things and have been working on shows for these few months too (extra stress). thoughts? I was thinking going to a doctor and getting on birth control would help with regulating? unlikely im pregnant, right?