could I be pregnant?

Jasmine
I have a 4 year old daughter , I was on birth control after I had her for maybe 2 years and then I got off it. My periods are becoming regular finally but I'm trying to figure out when I ovulated this month. September my cycle was 32 days long then 29 days in October, then 28 days November and 28 days again in December. So average ovulation for 28 days is 14 days which is January 11th for me (my period came Dec 28 and went off January 2nd) but my average days (from calculating all my periods is 29 days) We had unprotected sex January 11th and (he did not pull out). Then on the 12th I was cramping on and off for maybe a couple hours then it went away. Could I have ovulated the 12th?
. He also didn't pull out on January 3rd, 4th, 5th, and 7th, or on the 11th and 14th. Someone Please help me figure this out because I know ovulation dates are just estimates and can vary 😕 I've been slightly cramping on and off on at random times & Ive been cramping in my back here and there which never happens to me. 
My period supposed to start on the 25th, could I be pregnant?