In Need Of Help! Asap

[wishihad50k]

I need some help fast, I bought a 95 525i back in June w/ 160k miles on it as a family car (as my wife is pregnant. with our first) My mechanic told me that the car was in excellent shape and was taken care of, it just needs a tune up. I am some what handy with a socket set so I decided to do it myself. I bought some new plugs for the car (autolight something or another) and put them in. with in a few days the car started running like crap, it seems like I have lost most of my power under 3k rpms and the car hesitates when you hit the gas. Also started to here a loud tick tick tick tick coming from the engine. So I called my dealer and asked them what was up. I was told that the M50 engines are made to use a specific plug and in asking around here I found that this is correct. So I went out and bought the plugs from the dealership and put them in. While I was taking the old ones out I noticed 2 thing, one was that the plug end was a bit discolored (black) and two that there was a very small amount of oil around the threads of the plug (the car does not smoke at all and it has 160k on it so I figured that it was normal to see a small amount of oil that had gone past the rings) So I finished putting the new ones in and the car worked great for a few days... Now its right back to no power and hesitation under 3k rpms and the tick tick tick tick. I am so dumbfounded about what this could be because it doesn’t seem to happen as bad (if at all) when the car is not warmed up and it gets worse and worse though out the day until I park it and let it sit all night. I am freaking out because I have a new baby on the way and the bank account isn’t exactly overflowing. Another thing I have to note is that while I was in the engine bay I took the plug out of the MAFS while the car was running to clean it and put it right back in after I was done (the engine started to die but never did). Now I am getting the 1215 MAFS code every time I check it, should this have happened, does it need to be replaced, how do I reset the codes so I can see if it will come back on??? Please help me guys, any info would be awesome!!! thanks Ian