Dizzy since using sauna 2 weeks ago

41F, 175, 5’5”, I take prazosin prn for nightmares but have not since getting these dizzy spells because I don’t want to lower my bp if that’s a factor. I go to the gym a few days a week and use the sauna for 15-30 minutes, then cold dip for 2 minutes. I repeat this once or twice. I usually go first thing in the morning before work. 13 nights ago I went at night, I felt dizzy during the session and left early. I felt very dizzy that evening (spinning/rocking sensation, unable to focus my vision.) I assumed that I was dehydrated and that it would subside. I am still getting dizzy frequently throughout the day especially if I have been lying down and roll over or turn my head. The sensation is similar to when an elevator comes to a stop but lasts longer, or when you’re on a swing and the pressure/rocking you feel at the bottom of the downswing. When I close my eyes while it’s happening I feel like they re going cross eyed or side to side. Occasionally I lose balance or have to crouch down while it’s happening. I have history of getting mild vertigo very easily: if I am playing a video game and the character is on a high ledge or when I’m on some escalators and staircases. I’ve never been treated or concerned with that though, I assumed it’s pretty common. None of the dizziness/vertigo is accompanied by nausea, I have an occasional slight headache between my eyes or across browline. Should I go to a doctor or maybe try a motion sickness drug first? Thank you for any advice, I’m able to go about my day but not sure if I should be more concerned as it’s lasted two weeks.