No problem. The flashing red light simply means that the heater overheated.
This is most likely because the circ pump still had some air in it.
Shut off both circuit breakers, and put a garden hose down the gray filter standpipe. Turn the water on full blast to help purge the heating system of any air.
Then power up just the pumps (Supposed to be the 30 amp breaker...) But not the heater (supposed to be the 20 amp breaker...)
Wait until you see normal flow. This would be a flow of bubbles if your tub has ozone, or a slight rippling of the surface if your tub does not have ozone.
Run the jets for a few minutes, and then turn on the other breaker.