Ok, first of all, I'm most likely not pregnant, the chances are very, very slim, but I'm wondering if I am after all.
Have 21 month DS and a lovely DH. We'd like to TTC2 later this year after I've finished my thesis. Started pill (cerazette) in September because of heavy period pains, but missed one nearly every week in Sept and Oct. Started a new job at the same time, loads of late work nights, very tired, and DH and I weren't very active because of it (BIG understatement :)) and would use condoms as backup. However, we did it once without condom. Didn't think about it anymore.
Fast forward to this month. Had a lot more heartburn than usual, stomach felt "bigger" and thought a couple of times "Hmm, if I didn't know any better, I'd think I was pregnant", but knew that was more or less impossible, at least very improbable. Then, last night, right before falling asleep, I felt flutters in my stomach, loads of them, and they've continued here and there during the day. It might very well be gass, but then again, I've never noticed gass bubbles moving towards my hand. Normal bowel movements, not overly "windy", so gass seems a bit weird as well. It really feels more like baby movements. 
We decided to get a HPT, POAS and it's negative. However, I know that HGC-levels drop after about 16 weeks, and if I could feel baby movements, then I'd probably be at 16 or later. Can you still use a HPT later in a pregnancy? Can't find anything on Dr. Google. Would it be really silly to call the GP tomorrow morning, see what they say?