Watch problems after updating

When I installed the most recent update on my series 3 watch, it said i had to unpair and reset it. I did that, and now that it’s finished updating I’m trying to re-pair it. It says my phone is unable to connect to it and suggests that it may still be already paired to my phone, but i know it’s not because it doesn’t show that in my settings and my watch app looks as if I’ve never used it. My watch itself doesn’t turn on, unless you hold the circle button down and it asks then if you want to exit the reset. Other than that, the watch screen is just black as if it’s turned off. I couldn’t find any information anywhere about this, so I would appreciate any help! I wonder if it has something to do with my watch model being older at this point and maybe it’s no longer able to update and connect. Thank you in advance!