Appears to be a tapered crank setup.
Unsure if you have cartridge bearning setup of loose bearing (old school)
That ring appears to be the lock ring. Behind which there is the adjustable cup.
I'd definitely have a qualified LBS look at it.
Why? Because if the lock ring is moving it means the adjustable cup is moving and if that is moving you may have stripped threads in the BB. It may also mean that the entire assembly is really loose (at which point you'll probably be looking at a new spindle,cups and bearings) and has backed out to the point where only a few threads are holding the cup in.