I’ve read it can be normal to be lightheaded when pregnant but I’m just wondering if this happens to anyone else?

I actually passed out a couple weeks ago (while already sitting down). I took my blood pressure a few minutes after and it was 92/70. My normal blood pressure is around 110/70. I told my doctor about this over the phone because they aren’t doing visits right now. She thinks it could be all the blood going to baby and I wasn’t drinking enough water. I’ve made sure to drink plenty of water this week but I’m still feeling lightheaded at random times. No more passing out yet though. Anyone experiencing anything similar?