Hot Yoga made me sick

Mei Li, originally uploaded by Elspeth and Evan.

Today for the first time in ages i took a hot yoga class. I ate a meal a few hours before. I drank water, had some tea, i felt good.
At the end of class i was so fatigued, dizzy, and nauseous that i was worried i wouldn't make it out of the studio. I attempted to shower and it was painful. I thought i was going to have to tell someone because i might collapse. I didn't even blow dry my hair, all i wanted to do was get home and lay down if i could make it. It was freezing outside but i was still so hot. I am guessing my core temperature had over heated and roasted itself.. which is something that many people say is why we shouldn't do yoga in hot rooms. I just read this article and it really hit home. I have enjoyed hot yoga for over a decade now but after today i don't know if i want to go back.
http://www.pranayogacollege.com/writings/hot-yoga.php