Is it irresponsible for a mom to leave their child with a babysitter and go celebrate their birthday without them?

Backstory: I got pregnant when i was sixteen and had my baby right before i turned 17. I didn’t celebrate at all for that birthday, and since i’ve had my son, i can count on one hand the amount of times i’ve been out without him other than to go to work. This year, my baby’s father and boyfriend wants to take me out for my birthday for a “date night” and leave our son with a baby sitter.

Since then, his mom has been blowing up my phone and telling me how irresponsible i am for thinking about going out without my kid. Now i’m rethinking going out.

So, in general, is it irresponsible to leave your kid with a babysitter while you go out and have fun?