Blood Clots!! Help!!!

On Oct 15th I had a cyst removed from my vagina/cervix and I've been bleeding on and off. So then yesterday I started my period. But it was not bad! So then I was coming home from a friends house got half way home and I sat up and I felt like I had urinated on myself so I felt to see how bad it was being that I was wearing a pad so I put felt it and I brought my hand up and it was sticky and I realize I am covered in blood. Got home finally ran to the bathroom and my pad is soaked and I feel this like blob come out and it was a blood clot the size of a large egg and I was all freaked out!! I took a hot shower cleaned up and I wasn't bleeding bad anymore but I was still panicked! Anybody know why this may have happened?? Please help!!!!