feeling ill sometimes after coffee

Mommy
I'm 23 wks pregnant. I'm not diabetic. And never been a big coffee drinker. I've noticed that if I have a small cup of coffee at breakfast and have something small to eat I will feel ill within the hour. Not eating something small on purpose but I don't always have much of an appetite first thing in the morning. I will start to feel a little hot, tired like I need to lay down and my heart rate speeds up some. If I eat something and chill for a little bit I'll start to feel better. Could this be related to low blood sugar even though I'm not diabetic? I'll ask my doctor next week t appt but wondering if anyone else gets the same thing? If so, did you ever find out why?