Help?

[SallyG290]

Okay, so here's the deal.  My period has been fairly regular for a couple of years.  I'm sixteen at the moment, and for the past little while my period's come every 21 days.  In the past, however, it came ever 28 days.  My 21 day period was supposed to start on the 22 of August, and it never came.  Three - four days before that, though, I got cramps that felt like period cramps.  I took some pain pills and they went away.  My period never came.  I've had the cramps once again, but this time it wasn't 3 days before the 28 day mark.  I should be getting my period (if it's sticking to the 28 day cycle) on the 29th.  

Another thing to add is that I'm a virgin.  I've never had sex.  Fingering, yes, but my boyfriend assures me that he never touched himself before he did that.  I last got my period on the 1 of August, and I don't know if he fingered me between those times, but I can swear his pants never came off.  Some other information about me is:  I've been highly stressed for the past couple of weeks; I recently stopped taking some hormonal oils that help with period pains 'n' whatnot; I play sports; I'm 120 lbs and 5"5'.

I'm kind of scared at the moment, and any advice would be good.  I don't want to talk to my mom about it, and I would like to avoid taking a HPT at all costs, since it would be suspicious if I had to go buy one.  I've also heard that this could be a sign of something more serious.  

[SallyG290]

Yeah, I was just wondering what those reasons could be.  It's slightly disconcerting.  And just to note, in the first post I meant July instead of August.  >_>

[Kim1989]

your a virgin......so you dont have to woryr about taking an hpt

your still young and your periods sound quite irregular. if your worried then go to the doctors.. ther can be a number of reasons why your not getting your period