Over heating

[chumbucket]

Today, while out on the bay, I was running around 4200 RPM's when the motor just started sounding not quite right. It started rapping and just as I turn to have a look, the heat alarm goes off and all I see is steam everywhere. Like coming out of the pisser and from under the engine cowl. I shut it down immediately. The total time between the rapping and alarm/shutdown was probably 20-30 seconds. I raised the motor to have a look at the water intake. As I did, I saw something float away so I believe I sucked up a plastic shopping bag and blocked the intakes. The impeller and T-stat are new last year when I replaced my lower unit. After letting the motor cool down a bit, I started the motor. Got a little residual steam then water started pissing with a very strong stream. The motor rapped a little at first, then quieted right down. I ran it slowly for a while, no more heat alarm, so I gradually pushed the throttle a little at a time up to 4500 RPM. No issues.
My question is, does anyone think I may have caused powerhead damage for the short time it was overheating? I'm thinking not, but I get these weird scenarios and worry some thoughts running around my head all the time even when things go okay. Am I being paranoid? Should I have it looked at? Am I over thinking it? It ran good the rest of the day, so I just don't know.
I'd like to hear any thoughts or suggestions.