Everytime I eat or drink alcohol I feel sick, what could be wrong?

Enzymatic difference. One possible cause well documented cause could be the natural genetic variation in alcohol dehydrogenase. This enzyme's activity has naturally variations giving less in-born activity in certain populations. There is a drug called Antabuse (disulfiram) that inhibits this enzyme and causes significant etoh intolerance. So some people just don't tolerate etoh well.