Is this a MC or CP? Graphic photo warning

[Watermelonsug4r]

I had a MC in feb at 12 weeks which was significantly more painful and very traumatic.
I have been on the pill back to back for 2 packets just to try and calm my endo down that has flared up severely due to this, to stop my periods so I’ve not had periods since April.
I’ve not been the best at taking the pill because it’s not for contraceptive reasons as we have been TTC for a year and a half, so I have missed a few and taking them at the wrong time etc.
Bleeding randomly started heavily at lunch time today with some cramping and this fell out of me. It felt exactly like the moment my baby came out in Feb but smaller.
i have heavy periods with clots due to my endo and PCOS but nothing like this.
i hadn’t had a positive pregnancy test because I hadn’t taken one due to being on the pill. The hospital said it was negative and took a blood test to test for any remaining HCG but if it was a very early chemical would HCG still be there as it would be so low already?
it wasn’t a blood clot at all it was grey/pink tissue when I moved it to try and look

When did you go to the hospital? Was it recently x

Yes, they did the urine test about 6/7 hours after I took this photo as I was waiting a while x

I'm not a medical professional but I didn't think HCG would go that quick.

It doesn't look like a blood clot either. Did they say what they think it could be?

Blood clots from my v heavy period often look like that. I assumed it was just lumps of uterine lining tissue. Hopefully that is all it turns out to be for you.

I was thinking if it was a missed CP (my last miscarriage was a missed MC and the baby had died a few weeks previous to finding out) would the HCG not have already dropped significantly? I have seen a lot about CPs where the pregnancy tests go back to negative before the bleeding starts too and I have had one like that before but without this happening.
They said they’re not sure if it was a very early miscarriage and unless the blood test shows that it was then there will be no way of knowing x

Thank you. I get lots of clots and some tissue but I’ve never had it like this, it definitely wasn’t a blood clot and it was solid and heavy (for the size of it)