Ha, I am just below the age for giving the vaccine, but glad you think I am young.
I am pretty much like you, allergies, asthma (well under control, not an issue) and some subtle autoimmune things, mostly in my GI system. I have been getting these "flare ups" for almost 25 years. I remember the first one, when my younger son was 2, and coincidently, was at the same time I started teaching fitness classes. Hard exercise sets me off, but not always. I rested today, as much as I can at work, but no exercise. Funny, I ran, or ran-walked the past 2 days, because I couldn't sit on my bike saddle!
The bumps, except for this one, have been teeny teeny and never ruptured, either. But, I've had persistent burning and pain on my left side for years, mostly when I am getting better from an illness, cold, etc. I can feel the weakness on the bike, but I just deal with it.
Frankly, I am just glad I don't have MRSA. But, the bump is definitely not a boil, in terms of there's nothing there to drain. It's drying up today, can't feel it as badly. Now, I just have to fix the fricking blister on my left foot.
2015 Trek Silque SSL
Specialized Oura
2011 Guru Praemio
Specialized Oura
2017 Specialized Ariel Sport