Well im almost 17, and i know this is gunna sound bad.. but my brothers (hes 19) bestfriend whos 20 almost 21 have been screwing around, behind his girlfriends back. when this first started i wasnt aware they were together, but after a few months i found out. and that was on friday. He always said he used a condom, (several times i was sure he did, i put them on) but the times i didnt put it i know now he didnt either. my last period was January 26, im very regualar for the most part, 19-21 day cycles. so right now im at least 3 days late.. possible 5. i tested yesterday morning, i really didnt think i was possible pregnant till i had a yeast infection on monday and i read the box and yeast infections and pregnancy. so i just kinda want to know my odds at this point.. and if i should be worryed or not.