Feeling mucus in throat. Should i do?

I feel like there is something that feels and tastes like nasal mucus in my throat, which sometimes makes its way up to my mouth and tongue. Breathing feels a little blocked too, but what is strange is symptoms aren't very obvious, I just always feel like there's a taste of mucus or phlegm in my mouth 24*7 (no yellow phlegm or cold symptoms or coughing) My sister has told me on a few occasions that my breath is a little bad sometimes. Weird coating on my tongue too (very light coating at the back of the tongue). I'm very worried because it is not affecting me physically at all,but I am very worried and embarrassed about my breath and throat. I don't even know if I should go to a dentist or to an ENT specialist. Please help, someone? What should I do?