So.. I was playing this other MC server and I found two spawners together.. I let them build up on purpose while being safe. (They were cave spiders) I broke a block to kill them and I started to lag.. Like 5000 cave spiders swarmed inside my safe spot. I logged off, I went on a bit after and they were still there :/ How long does it take for them to un-spawn? My diamond armour isn't eating all of their attacks and I'm like 4 hearts.
Try logging out a few more times, or going more than 32 blocks away from them and waiting. If you're 32 blocks or more away, they should disappear after a while. Of course, that'd be a problem if you can't escape... Good luck
I got out! When I came back they all had spread or something.. I did /f home... and waited like 10 seconds(you need to wait 5 without moving to teleport) in the lagg and logged out. When I came back in I was in my base with 1 1/2 hearts xD