Should I get a second opinion on this felling of lump in my throat my doctor only felt of my neck and look in my mouth and said everything was ok?

Yes. You would be wise to have a second opinion by either an ENT or oral surgeon to make sure that the lump you sense is rally not there. Certain types of "scoping" examinations are the only way to truly determine if what you are sensing is of consequence or not. Get it checked.