Take a rest. Like a 1 month off the bike type of rest.
I did a similar thing to myself about a year ago when I was between jobs, started riding to fill the void, then more and more until I was doing ridiculous (by my standards) weekly mileages and climbs. Got to the point where I felt just amazing doing anything and my back was the best its ever been (thanks to lots of regular time in the gym at the time).
However, if someone in the next town sneezed, Id get a kicking cold that would render me useless for 5 days at a time, when normally I have a bosse immune system (only 1 sick day in 11 years of working + uni). Doc said take a break, I did for 2 weeks, didn’t do anything. Tried again for a month and that sorted it, haven’t been ill since.