12 Days late

Ok so I was suppose to get my period on the 25th of November I usually always get it on the 25th or the 27th of each month.
I am now 12 days late, I've taken 4 HPT and each one said negative. my nipples are a little tender and I notice today around them they are a little darker, expecially around the bottom.
(my periods are never this late) Could I possibly be pregnant?

[Heather5]

I would wait a few more days and test again. It could be two different things...either you're pregnant, or you might have ovulated later than normal this month. Best of luck to you!

[Beaver13]

I am very late also and this is my first run on clomid 50 mg , im very nauses but breast arnt tender, took a pt on 2nd day i was late it was neg, and i still havent started, could it all just be in my head cause i want one so bad!