Hot pulsating feeling in thigh/butt?

I’ve been experiencing his hot feeling in my upper thigh/butt that lasts a few seconds and then goes away, on and off for 20-30 minutes. I first thought it was just that I had been sitting for too long but it can happen when I’m standing or after I’ve moved around too. It’s the same spot every time. No pain, just feels like something hot touched me in this one spot. I’m only 13 weeks so think it’s too early for sciatica or baby pressing on a nerve, but I don’t know. Anyone else experience this and know what causes it?