Unless your wiring was damaged or sketchy, it will have no issue taking 20 amps for a while. Problem is a (small) chance it could in fact cause issues, possibly

Unless your wiring was damaged or sketchy, it will have no issue taking 20 amps for a while. Problem is a (small) chance it could in fact cause issues, possibly fires, possibly at a later date. People don't usually count consumption of their devices, so plugging in pretty much anything that the circuit breaker will take is a fairly common occurrence.