Yes, I have the exact same thing. A nasty thick phlegm that is difficult to cough up. Mine has gotten worse to the point its difficult to take a deep breath without coughing. Now I have a chronic cough and difficulty breathing.
It turns out I had been smoking some bad meth
that was cut all to hell. I never called that guy again and got a new dealer with much better gear. Methamphetamine
won't do this, it is highly water soluble and the natural moisture in your lungs is probably enough to dissolve it well.
The cut is a different matter though. Good meth should not make the stem of your pipe look like its coated with a thick layer of white chalk dust. I think that's what the inside of my lungs look like. LOL
Recently I researched how to clean or wash my meth. I have been unable to find high quality meth that's not cut. Just a simple acetone wash works quite well and can make a big difference. I would HATE to get lung damage from this shit, and I'm sure you would to. I suggest you do the same and check out cleaning threads on DF. If you have trouble finding them, PM me and I'll send it to you.