Very hungover thanks to a drink or two after a 3 month break from alcohol.

I, 21f, have never had a problem with drinking or hangovers. I’m a lightweight and I’ve never really drank more than I needed, even on a night out. About 3 months ago I was in an accident involving alcohol and decided to take a break from drinking. I was completely sober until recently, when a friend came to town and I decided to have a drink. The next morning I had terrible stomach cramps and a headache. I figured it was not related to my one drink, as I’ve never had a hangover, and instead attributed it to PMS. That was until this week, where I tried drinking again two separate times, one night I had a few ciders and woke up to the same symptoms that lasted all day. Last night I had a glass of whiskey, and again, woke up to terrible stomach pain and a headache that have both been bothering me all day. Why is this happening to me? Did my break from alcohol cause me to develop an intolerance? I’ve never had hangovers in the past after consuming much more alcohol. Has anyone experienced anything similar? Do I need to go back to being sober?