I usually get my period 28 to 42 days but now I have been waiting 56 days

I was with a boy, he said that he would just put his penis in me and take it out straight away just to see what it feel like, I didn't want to do it at all, I didn't feel comfortable with it, I don't know if he had sperm on it before he put it in me but straight away I regretted it and told him to stop!! He said ok then could I just give him a hand job instead, so I agreed so I wouldn't have to have sex with him, he also fingered me at the same time, but I usually get my period 28 to 42 days but now I have been waiting 56 days, I'm really scared that there's a risk of me being pregnant, he said he didn't discharge in me but he did after and he had to put his penis back in his trousers and he touched me vagina! I'm only 16 and I know I was so stupid, but I felt pressured,I have been having stomach pains and feeling sick but no period is coming, please HELP ME!! I'm in desperate need of advice!! I don't want to be pregnant!!