Coughing for 2 months..?

[PB96]

So.. I've been dealing with some other health issues, cysts in my thyroid gland, myoclonic jerks and twitching (the latter might just be BFS).
But I've noticed over the past couple of months that I've been coughing a lot. I didn't feel sick at first. Then om holiday, I felt really bad, with vomitting and so on, and coughed frequently. I got better, didn't went away completely, then came back a few weeks ago. Got better, now beginning to worsen again.
I don't feel ill, an according to doctor's tests, no infection. But some clear or yellow phlegm do come up sometimes.

So why do I keep coughing more or less? I'm beginning to worry a bit.
No allergies, no asthma, no genetic diseases known.
I don't smoke, never have.

[specialmom]

Coughs definitely can linger. Once the bronchial tubes in the lung are irritated, it takes a while to get over it.  And some develop a temporary asthma.  Production from the cough is not uncommon as remember, the body responds with mucus when there is irritation.  It can take a full 2 months to get rid of a cough.