I'm responding with my views based on my step DC's.
Three of the four would go out and stay out, often returning after a hospital visit, needing collecting, having signs of injury, police involvement. One now has a criminal record.
A night out escalated into staying out all night, grabbing some breakfast, then continuing to drink. They would go missing for days at a time, able to travel by bus or train from town to town, but not coming home. One slept in the station, one was found by one of our friends wandering our town, 'new' friends attached, days after going missing. We wandered a city looking for another.
One step-DC is fine, can go out, drink, party, be drunk, but stop when they've had enough. Normal drunken teenage stuff.
The other three, just not normal behaviour.
They have realised they just can't drink at all. Really no 'stop' button.
Dangerous in terms of losing property, being beaten up, falling over, being taken for a ride by others ( huge spending in pubs by 'friends').
Their mum has had issues with alcohol.
As late 20 year olds, they don't drink at all. They know they have alcoholic tendencies which can only be controlled by not drinking. One pint and that's it...
Scary stuff.
OP please watch and see. There is a marked difference between my four step DC's in their ability to control alcohol.
Does your DS have a stopping point, without it there are concerns.