On one end, I could see the difficulty of taking those two classes at the same time. But, in my case, I took the MCAT a full three years after taking those classes, and while I still got a 35, it took a LOT of making up for lost knowledge. If you're taking physics while studying for it, the hardest part of the physical sciences for many would be in stride, so I would say if you feel like you can handle it go for it.
Mission Failed:
"Stop kidding around....... Snake?!?....SNAAAAAAAAAAAAAKEEEEEE?!?!?" -Otacon
DW