When does the follicle go away?

Vi

So I had an ultrasound done today and the tech said she saw multiple follicles on each ovary, and a thick endometrium lining. She didn’t explain much but is it safe to say I probably haven’t ovulated yet? I had horrible cramps yesterday and part of today. I got my first positive opk on Sunday, today it’s negative. Everything I’ve read says the follicle disappears after ovulation.