I believe you acted in the correct way. The only time I would switch to 121.5 is if I was in a remote area and not already talking to someone.7700 is a bit academic in your situation, you were in the vicinity of an airport, already talking on the radio, and I think using 7700 would probably cause more fuss than nescessary (its not going to re-start your engine for you
).
However had you squawked 7700 and landed safely at an unciontrolled field, it would certainly be worth a call on the RT to the local approach control / centre frequency and tell them you made it down ok. If you can't raise them, possibly ask someone to relay your msg, or if there is no one, a call on 121.5 and ask to relay, or finally a call from a good old fashioned phone to either the tracon / centre / 1800WXBrief.
Cheers
EA
