Workout made me feel sick to my stomach? Is this normal for beginners?


So its been about a solid year since I last started a serious workout routine, and I'm dealing with about 20 extra pounds of body weight than I'm used too. I've gave myself about a week to change my diet, before I started the fb 8 week program (today was the first day). I've been doing some light yoga, and I'm moderately active at work (always on my feet walking or standing) -so I'm not completely out of shape... at least I didn't think I'd be "out of shape" enough to make me feel physically ill during a workout?

I've been eating way cleaner than I normally do, so I don't think its the food?... But about 10 mins into my workout I started to feel almost like a heart burn feeling right underneath my ribs, that slowly progressed into nausea. I am really good about knowing when to back off, and take extra breaks during a workout if needed, but it didn't seem to matter. I usually feel really good after completely a workout but I was so out of it I barely made it through the stretching (something I have always looked forward too). I'm wondering if this is normal, and maybe just a consequence of elevating my heart rate above normal? I'm not sure... If anyone has experienced something similar to this I'd love to hear some tips on how to get past this portion of a new workout routine. The nausea seemed to dissipate quickly upon rest (about 7 mins).

For breakfast today I had some oatmeal with sweet potato mixed in, and some Tahini/spices. I had snack of some wasa crackers and a pea dip I made, and I had an orange about 30mins before working out, and earlier I had half of a 16oz vanilla latte from Starbucks (a habit I'm trying to break, but I know this would't make me sick, and I had less of it than normal). I have yet to have dinner, but this is a lot cleaner than I have been eating? So I think I can rule out food as a cause?