I’m confused

Lastei

So I had sex twice last month and both times were after my period with a condom and my partner did not finish. This month it says that my period is 7 days late, lately it has been always early though. So I decided to take a test just to be safe… I ended up taking two and they were both negative. Today I’m 8 days late it’s never been this late, my boobs feel sore and I’m just super confused is it just stress should I be worried,?