Brief history, about a month back I changed my oil and filled coolant (followed up a few days later and verified levels were still full). I have been experiencing an issue with my 2011 Grand Cherokee Hemi with a random rough and surging idle. First few times in they did a computer update and some random BS but the issue persisted.. finally a check engine light threw and after a few days they said they narrowed it down to a bad fuel injector. The service manager advised I should get my spark plugs changed and it was about time for my 32k service anyways. It its been a few weeks and the rough idle appears to be gone, but we have only been driving lightly and occasionally... and I just got around to changing those plugs. When I pulled the last one out I noticed it was a bit wet on the threads and appeared to have some oil on it. Upon checking my other fluids, my radiator reservoir was about 75% empty and my oil had dropped just below the min/max lines.
My poor motor knowledge tells me I may have a leaky head gasket? Or is a bit of oil on the plugs normal? I haven't noticed any smoke or anything form the exhaust... so I'm not sure if I'm burning fluids anywhere or what.. or maybe I'm just crazy and I never measured right the first time and or lost some fluids somehow when it was in for service.
Anyways, basically I want to know if I should haul it back in. Its my only vehicle so it costs me a rental car when I do so.
Also, if it matters.. I'm in Arizona.. so its a million degrees all the time. I'm fairly sure I'm not leaking oil.. but if I was slowly leaking coolant it may be burning off too quickly... also have the trail rated package.. so skid plates could be intercepting some of it I guess.