Why do I get sick from so little alcohol

Throwaway because my main account is linked to my name. I am a 23 year old female who has a pretty terrible alcohol tolerance. I’ve always known this but I’m wondering if have an alcohol intolerance. There has been multiple occasions were I will drink some and feel sick hours later. This happened again tonight. I had two drinks with my dinner tonight, which was more then several hours ago, and feel terribly nauseous now. I thought I felt fine whenever I had the drinks and did not feel nauseated the first few hours after having them. For context, the drinks were not drunken quickly and I did not have an empty stomach when I had them.