T2
You do, of course, now have the right to look at your Medical Records and have them "corrected". Now they're held on computer I think I'm right in saying an alteration leaves no trace of the previous "opinion". If you've taken the trouble to build up a decent relationship with your GP (most people don't, but IMHO it's well worth while, certainly where any sort of flying is involved!) the latest episode could be "reconsidered". These days GPs are well aware of the implications of labelling patients asthmatic and most GPs would certainly be happy to discuss the problem with you. At the very least you need to know what your record says. Early childhood episodes are common and would probably not be relevant.
As someone has said: "Don't ask, don't get". Consider it the first part of your initiative test!