I think I have dry nose and I'm not sure what to do?

[Jeden]

So it started out with coughing out phlegm. Then my voice became rough and then I developed a sore throat. So I took some drinking medication for the cold-flu and coughs, to cure my throat. It didn't work.
Well after a day or two of completing the medicine, I got dry nose condition. Everytime I breathe, I feel my nasal passage getting dry which is a very uncomfortable feeling. I felt the inside of my nose and noticed there were dried mucus. Now I got a sore throat and a dry nose. I keep swallowing saliva whenever my nasal passage feels dry and thats almost every minute or so.
I considered getting a nasal spray but I wasn't sure because I never used it before and I worry I might worsen my sore throat.
Please help me, I want to get rid of this dry nose condition, it's been preventing me from going to sleep. It's been going on for a week now. Any suggestions would be appreciated!

Also I am not sick, I don't have a cold so I still don't know why I developed these symptoms. The coughing of phlegm may have something to do with it.