Pregnancy question...not sure what's going on...?

Last month my period came at 24 days, but really full on at 25 days (usually I'm 28 days, very rarely not so maybe the brought it on). I had unprotected the day before I got my period. I have had 2 instances of unprotected (used pull out but not sure if he did all the way) since my period was done. I am currently on day 25 of my cycle. Weird thing is...I've never had a period where my didn't hurt before. Last month they did not hurt beforehand (maybe slightly), and now this month they do not hurt at all either...usually I get VERY sore for a full week before. I feel dull aching in my lower abdomen but not exactly what I would describe as menstrual cramps...feels a bit different. Doctor gave me 2 pregnancy tests because last week thought I was having a gall bladder attack, bad side pain but that's gone now. They were both negative. Not sure what to think? Any ideas from anybody? By the way, please be respectful as I am only asking for advice and am mature enough to take responsibility for my actions. Thank you :)