Is $1,800 a lot in credit card debt?

It depends on how much you make and how long you've carried it. If you charged $1800 for a water heater and pay it off in a couple of months, no big deal. If it's a 0% promotion, no big deal.

It depends on your situation. If you don't have the ability to pay it back, then yes, it is a lot. Otherwise, not really.

Not a significant amount but ideally, you should be paying it off completely every month. Pay it down and don't think of charging anything more until you have paid it off, in full. Good habits are - good habits. Get in the habit.