I was in the AF for 5 years as an engineer, and got out in 2005.
What career field did they put you in? Regardless, I wouldn't wory about not having any engineering experience. Being in an "engineering" job in the Air Force really doesn't give you any "engineering" expereince anyway. Most of the guys I knew who were in "engineering" jobs were more like program managers, and rarely used their hard core engineering skills.
As far as the clearance goes, basically all that does is makes you eligible for more jobs. There's tons of jobs out there, both working directly for the government (as a GS) and working for governemnt contractors, that require that you have a security clearance, and you can't even apply for them if you don't have the clearance. There's several differnt sites out there dedicated to recruiting cleared personnel, one of them is ClearanceJobs, I think.
The important thing to remember about a clearance is that it does expire. If you're not in a job that requires your clearance for more than two years (I'm not sure if its exaclty that time amount, but I think that's close), thenyour clearance goes away. And once its gone, its basccially like starting all over if you need to get it again.
So, bottom line, check out the jobs that interest you. Having the clearance makes you eligible for more jobs, so check all of them out.