Passing actual tissue no picture but still TMI

I know I couldn't have been more than 3 weeks pregnant, I believe I might have had a chemical pregnancy because the test lines got lighter and lighter and then negative and then I got my period. It started out light, I didn't need a pad at all and then bam I go pee and stuff came out of me. It looks like skin, it's almost white and has veins in it and it's quite gruesome looking. I always have blood clots and uterine lining on my period but this looks completely different. It's worrying me. I don't know if I should like bag it up and go to the hospital.  I am not really in any pain, just mild period cramping. I feel okay. It's just what I'm passing that's freaking me out.