Yea it sure kicks your butt. I had walking pneumonia in 1982 or 1983 and was working on new homes out of town. To save money I would stay in a sleeping bag in the units that got hot water and gas for heat before they were ready to move in. Saved lots of money and had a small 13" tv so it was great and I gt a great write off on all gas, food etc. But was having to take my boots off all the time because subs were going into the units with mud and getting it all over the new carpet so the was cleaning the carpet so it be wet. Then going in and out all the time like that got to me. I stayed there two day before I said I need to go to Kaiser to see a doctor. So too the 145 mile drive back home and then my dad took me. I was so sick that it did not hit me that Kaiser was all over the place and they had one right down in town where I was working. Said to take 3 weeks off work but I took a weel and went back because I was making so much money back then I did not want to take to much time off. But I was never the same after that. It takes so much out of you and maybe if I did what the doctor said I would of been better.
So just do as the doctor says and take it easy because your not 17 and may not ever get all back to being the same as you was before getting pneumonia.