When To Worry?!

Jasmon • FTM💙 EBF🤱🏼 fur mom🐾
Just a warning: I have no filter.
Okay so I don't want to sound like an uneducated adolescent. I know that the female body is weird, and can do stupid shit, such as miss periods and such for no apparent reason, but my SO is stressing, which in turn is stressing me out.
So.
Last month, on October 8th (YES I keep track), we had a lot of sex, to put it bluntly. There's a SLIGHT possibility that the condom broke, because we were going for a pretty long time and the lube wore down, and when we were finished I had semen on my leg somehow (there's a diff trust me). I started my period the next day, and had it for 4 days (that's normal)
Now here's why he's stressing: here we are, a month down the road, and no period. It was projected to start Saturday, nothing. So I figured it was slightly off. Sunday, nothing. Monday? Tuesday?! Nothing. Wednesday (the day it should've ENDED), nothing. I have no period symptoms, usually before my period I get really bad migraines and back pain, and get very bloated right before I start, but there's been nothing.
When should I start worrying about being pregnant?
When should I test?
Any other tips?