What’s endometriosis like?

Many of my periods, for whatever reason, the first night (like when I’m laying in bed) I get terrible burny feeling cramps. Sometimes they go away after 30-45 mins, sometimes I take ibuprofen for them. But then the rest of my period is fine.

Last night was the first night of my period and I had the most excruciating cramps of my life, I was up for a couple hours in the middle of the night and ibuprofen didn’t help. I was deep breathing and it was just so bad.

They finally went away and I think I’m on track for no more cramps the rest of my period (4/5 more days).

Is this any sign of endometriosis? Or does endometriosis hurt during the whole period? I don’t feel pain the rest of the month or during sex at all.

Thanks for your answers!