My anxiety is driving me crazy!

I knew one day, when my partner and i were having sex that maybe something would happen and i would end up pregnant. So i took precaution and got the shot last month on the 12th, lol i know that he doesnt want anymore kids and i dont want any at all. we had sex on the 17th and tada! he ejaculated in me. i knew then and there that i f@cked myself over officially especially with my anxiety. but i stayed calm and went to the pharmacy that same day and bought plan b, but even taking that my mind still isnt at rest!

Lol its october 9th and usually my period would be on by now or ending. I dont wanna start freaking out because something like that has happen to me before. I want to take a pregnancy test buuut im scared that im pregnant, etc. etc. I dont feel any different, except a bit gassier than usual and i think its because of cutting out beef and pork from my diet. Anyways i could use some advice please and thank you