Hey I Need Some Help. My Boyfriend Fingered Me Two

hey i need some help.
my boyfriend fingered me two months ago and since then i am not having periods. i dont know if he had touched his private part before fingering me, he says he did not and that i cant be pregnant. instead of periods i got brown tissue like discharge in a very small amount for 5-6 days. then last month he fingered me again and i got the same type of discharge for 5-6 days. i took pregnancy tests they were negative but yesterday and today i took a test again with a strip of a different brand and there was a faint pink line . am i pregnant?
my periods are not regular but i started getting them every month since last year.
i am not feeling nausea or dizziness. my belly feels a little blotted but it could be due to not having proper periods. and i get cramps in my belly and back.
i have been taking vitamin e for two weeks for my skin.

is it safe to take vitamin C to induce a natural abortion?