Please consult a Urologist BEFORE attempting to do anything suggested off the web. After reading your other posts sounds like it is time for a circumcision IMO.
UK. My nephew had similar at same age. They simply circumcised him. Problem solved. But if this has only happened within two years, then it really does need medical attention. How can you only think you had an infection? Was it not verified and antibiotics prescribed? But, even so, if this is the result of an infection, and the infection is not ongoing, circumcision should sort it out. It's only going to get worse. If you can't access all of your willy, then you can't clean it properly, and further infections are likely. If the nature of the skin has changed - hardened, as you say, this has an underlying problem that needs investigating.
Luck.
Have a search around pegym, I do think I have read something about it on the under genral discussion, I do know there some exercise's for growing a foreskin, so these may help in streaching it sideways to help incress its circumference.
Good Luck