38 weeks pregnant, food is making me sick?

I really need some advice... I was going to ask my doctor next time I go, but I figured somebody could give me an answer now. I'm now 38 weeks 2 days pregnant, and about a few days ago I noticed that certain things I eat make me sick to my stomach while I'm eating it, like I feel I need to rush to the bathroom to puke, but then the feeling goes away in like a split second. Now it's beginning to do it over everything I eat. And the other day, I started feeling major sick like I knew I was going to vomit for no reason, just completely random, and I rushed to the bathroom and had major diarrhea. I thought I was going to be fine after I was done, but thankfully the trash can was next to me and I puked up everything I ate for dinner, which was food from 2 hours before then. Afterwards, I was perfect. I waited about an hour, and ate some Mac&cheese, and nothing happened at all. This has happened once before a couple of weeks ago, but I didn't actually puke, I just had the diarrhea part, then got really dizzy afterwards, I laid down and fell asleep for an hour and woke up, I was fine. I told the nurse when I went in my appointment last about the puking and diarrhea, and she just didn't say anything... I don't know what's going on, but has anybody ever experienced this before? If so, what could this mean or be from?