I'm going crazy with these mucus probably. The child has a stuffy nose…

I'm going crazy with these mucus probably. The child has a stuffy nose. I drip Aquamaris and suck it out, but I won't get all of it. There are some mucus in his throat, ? because of that he has trouble swallowing milk ? then he gets nervous and cries. I haven't slept for 4 days. Maybe stop dripping this Aquamaris? I don't know what to do anymore, it hurts my child.