Thoughts?

Ok i just ended my period 3 days ago and my periods usually lasts for about 5-6 days but this one only lasted for 4 days. An im usually pretty regular. Me an my fiance had sex last night an afterwards there was light pink when i wiped with some sharp mild cramps. My question is if i could be pregnant? I didnt have many symptoms of PMS during my cycle but am starting to have really sore nipples and am extreme fatigued.