Help!!!! 2 day period? Could it mean something????

On October 10th we had sex and he finished inside. Around the 23rd of October I had what it looked like a 2 day period. Never in my life that has happened to me. It’s just weird cause my period always last about 5 days. And it looked like normal period. Today I’ve been feeling like types of cramps and every time I laugh or sit on the floor my lower belly hurts/bothers. My last normal period was September 18-22. Someone please help!!