Should I see a doctor or will this go away on it's own?

I do not have a cough at all...I can breathe fine and all that but I have a mildly sore throat and it's full of phlegm ...some is green but some is likt dark orange..Sorry I know it is gross...It feels more full of phlegm than sore but it is kind of sore too...Like I said no cough or anything btu I also have had a little bit of nausea the last few days...Could this be strep throat or somethign? I haven't been sick in years I don't know all I know is I have no cough so it's not a cold or bronchitis