As long as you use water, not a wooden scoop or something, you shouldn’t have any problems with damage. My dad DID have his ears irrigated and the doctor used a hook. That seems weird and potentially dangerous. I use the over-the-shelf stuff and it’s quite safe.

Some hearing loss is permanent and some isn’t. Basically, be more conservative with your exposure and if the tinnitus goes away, it wasn’t permanent! Rock bands are especially difficult because you tend to stand close to drums and the guitars are distorted, making the high decibels more destructive. There’s not a whole lot to be done. I would, however, recommend cleaning your ears with a solution and syringe system like Murine. That’ll help keep things clear so that you’ll be better able to discern what’s causing problems.