Did the notifications system change? I haven't been on for days and I have 0 notifications. It Seems like I should have some from people posting in groups I'm in even if no one interacts with me or my posts... Usually there are many after just a part of a day.
Just tap on the bell-shaped icon in the upper right...it is not very responsive since the site grew so much.
Click "view all" .. you should have plenty of alerts...
You probably have alerts. I'm getting alerts but not the little red dot.
Instead of clicking Edit, you may have clicked on "Turn off alerts."