Ice cream and alcohol?

I turn 21 officially tomorrow, my plan is to go to a sushi restaurant and get some sake and a beer or two

My want for dessert is sundaes, I’m a little lactose intolerant but I have the pills for it so I’ll be taking those of course before I eat ice cream but, my question is

Has anyone had any bad experiences (sicker, pain, more of a hangover, etc) with eating ice cream while smashed?

I googled it and get various results but not exactly what I’m asking. Most of them are if you can mix them in the same dish, which I know you can, mine is… does it irritate your body more type thing

Also any recommendations for cocktails or beer that you guys really like? Ive been drinking for a long time but the whole “21” thing is exciting lol