Is this post nasel drip or something else?

So I’ve had that cough for like 2+ weeks now and it’s getting very annoying. Last week I could barely breathe without having to cough. Chest felt tight and that tickle in the back of my throat was constant. Been taking mucinex and trying hard to cough up phlegm.

At night when I get into bed is rough. I lay down and instantly I start coughing and have to get up cuz I can feel the mucus in the back of my my throat. All week I have been just getting up and going to the bathroom to force myself to cough up phlegm. Yesterday I thought I had a break through. I coughed up a big phlegm and I thought that was the main culprit. Went to sleep fine and woke up and I felt like something was in my throat. Almost like you’re eating and something’s stuck there and you need to wash it down with water. Tonight I just went to the bathroom and forced myself again to cough and basically threw up and a lot of phlegm came out. Felt like I emptied the tank with that one. I would take deep breaths and wouldn’t feel anything in my chest and no coughing.

I got back into bed and I could feel mucus running from my nose into the back of my throat again. It’s been like 15min and that “something stuck in my throat “ feeling is back. Not coughing rn but I could feel the build up again.

What is wrong here? Should I just go to the doctor tomorrow? Will they be able to give me something to make this go away?

I am M30 5’6” approximately 150lbs.