After years of testing abuse I have areas on my fingers that are leathery and puffy & produce no blood unless I really crank up the pricker.
They do seem to recover a bit if you leave them alone for a while but its harder these days as all testers seem to prefer top finger sides whereas it used to be a mix of top & bottom giving a chance for serious recovery when you got a new tester!
Warm water & waving is the best I’ve come up with but lack of blood I take as a warning of damage, I’d talk to a doc about where else you could test.