Is conception on day 19 of cycle even possible?

I know there is no way that you guys could possibly answer this... but I really need to run my situation by some other people... just to get some feedback...

I have a very consistent 27 day cycle. I get insanely sore breasts and nipples around ovulation, though I have never tracked the exact days that this usually occurs during my cycle before. My husband and I had unprotected sex on day 19 of my cycle, which would seem pretty harmless, except that day my nipples had started hurting horrendously, as they usually do around ovulation.

Now my period, which is never late, is now 2 days late. And I always spot for about 2 days before my period, so I know its probably not coming in the next day or so, since there has been nothing.

I did take a HPT yesterday and it came out negative, which makes sense cause it wasnt 10 days after that 19th day.

So what do you think? Im mildly obsessing over it, which could be causing the delay as well... What do you think the chance is that this resulted in pregnancy? I know there is no way you guys could actually know, but I would love a little feedback on the situation.