I had sex a long while ago when I was on my period about 2 months ago now... I took a plan b during that time ( I just got worried and wanted to be extra cautious)

A few days later when my period had already ended, I started light bleeding again for 3 days then it stopped. I waited tll my next scheduled period and it didn't come so I got worried of course and took 2 tests a week later. Both negative.

So I decided to wait it out more and now I am coming up to my 2nd scheduled period, since that time taking the plan b should've happened, and still nothing. I took a test yesterday again. Negative. I am 40days late and I am experiencing no symptoms so I have no idea what is going on.