It is unlikely that asthma would “turn into” PH. What may be the case is that you have two lung conditions, or as you suggest, that your symptoms were in fact due to PH. Without the details of your case I cannot comment specifically on whether either of these is true (or another explanation altogether). However I will say that it is not uncommon that PH goes undiagnosed for years before the correct diagnosis is made. That is one reason we are working so hard to raise awareness about the disease – to physicians and non-physicians alike.