Fermentation problem?

2 weeks ago I started an oktoberfest brew. The primary fermenting seemed to go well, I started it around 4pm and made sure to wake up in the middle of the night to make sure that I got it into the garage as soon as I noticed the fermentation begining. I put my carboy in a fridge that was/is not plugged in not taking into consideration that fermenting produces heat. When I woke up in the morning the temperature was a perfect 50-52f, when I got home around 6pm the temp was up to 64f, I hauled ass to the store and bought ice to cool it down as fast as I could and just left the carboy in the open in the garage and the tempurature was perfect.

After 11 days I siphoned to my secondary, it tasted good as far as I was concerned. My og was 1.060 when I measured the gravity it was 1.041~. Now my concern now is that thursday the temperature went from about 40f in the morning to about 85f and my brew was at 62f AGAIN! So I hauled ass to the store again and tossed a couple bags of ice and my secondary into the unplugged fridge again. The temperature is once again a perfect 50f-52f but for the past couple of days I have not noticed any bubbles in my airlock and my brewing instructions say that it should take up to 5 weeks for the fermentation to complete.

Have I managed to screw up my oktoberfest? Are lagers so tempermental that any temperature change will kill the yeast or cause off flavors?

The oktoberfest is my 3rd batch and I am afraid maybe I got a little presumptuous

First off you took the yeast away from the healthy primary cake before fermentation was complete. Not good. If you want to wait for the secondary yeast to complete fermentation, you'll end up with a stuck ferment.
Try pitching more yeast to see if it will pick up or you can do the swirl and raise the temps a little to boost activity.
Try to keep your temps steady, yeast don't like the changes.

Should I raise the temperature back to the mid 70's or should I keep it a bit lower to avoid getting off flavors?

Keep striving for the recommended temperature range. You had a very active fermentation, hence the heat it was creating. Sounds like it's progressing just fine. You probably shouldn't have racked it so soon, but otherwise, all is well.

In the later stages, you will see very few bubbles, particularly since you racked so early. Keep the temperature down and let it ride.