Not sure if it’s hives or heat rash .... hormones?

Third pregnancy and never happened before but for about a month I’ve had a rash all over most of my body. Mostly on full arms and thighs/legs..with a little on hands and feet.

Heat makes it worse but it’s also flared up when I was indoors and it was cold inside. I took some skin cream my dermatologist gave me that’s safe and it went away for a few days then popped up again.

It’s been coming and going for about a month. Sometimes my whole body and sometimes just certain spots. Bumps/Small welts looking like mosquito bites also surrounded by little bumps that look like razor bumps and red areas come up .. extremely itchy and painful

I’ve read a few things online about itchy causes for pregnant women but it doesn’t seem to fully match up with what I have. Maybe hives?

I called my dermatologist and gynecologist for follow up appointments but just wanted to get some thoughts from everyone here. Currently 24 weeks pregnant.

Thanks!