I Don’t know what this is!

I’m 13w+5days and tonight while using the bathroom this little tissue came out of me.. I’m very much constipated but I wasn’t forcing anything to result like this.. I haven’t had spotting since my first trimester and seeing this grayish tissue it has me really worried.. I’m Not bleeding or spotting just cramping a little bit do I go to the ER or call my on call doctor? I’m a first time mom so this is very scary and new to me. I’m still feeling my little flutters here and there which is only giving me some sort of comfort