Nearly fainted in hot shower—did I harm my baby? (20 wk pregnant)

Enjoyed a spa day today and was loving the hot shower afterward when I suddenly started seeing stars and nearly passed out. I realized a bit too late that I must have gotten overheated. (I usually take pretty warm, 20 minute showers at home, but I never feel overheated or dizzy. My home shower head dumps water at an angle—the spa shower had one of those overhead rain style shower heads, so I feel like I was much more enveloped in the hot water than I usually would be at home.)

I turned the water to cool and noticed my skin was very pink. I sat down and let myself breathe for a while until my eyesight started getting back to normal and I felt more sure I wasn’t going to faint. I felt a bit nauseous. It took me about 20-30 minutes to fully cool down, and I felt exhausted afterward. A few hours later, I’m feeling back to normal. And baby is moving around normally.

I’m just feeling a bit worried. Did I harm my baby through this heat exposure? I’ll be getting my 20-week ultrasound this week, so I’m hoping I’ll feel more peaceful then. Thoughts?