Training 3 hrs at a time is just going to make you tear down your muscle beyond repair. I am surprised you are not losing muscle and strength. I used to do this too. I was training like this for a little while when I was a couple years younger. I would go and lift weights for an hour and a half then go from the gym, grab a protein shake and head to the MMA gym. We would train MMA for 1-2 hours. I would go home and practically collapse for the night. I was losing weight (muscle) and felt like shit. I actually depleted my muscle glycogen so bad I started to have prediabetic symptoms. My blood glucose would yo-yo up and down. I finally started to fall apart. I went to the doc and had all kinds of tests done everything came back normal. I cut the training back but I still have to deal with hypoglycemia quite often and I honestly believe that it was from training like this for too long. Anyway don't let your body get to this point. When you body is getting overworked, it will send you signals like you described. Don't ignore them or you will be sorry. I learned the hard way. I always listen to my body now. If you fix this, I think your problem will be solved. Best of Luck.
