I have had most of the same symptoms for the last several weeks, as well. I'm assuming it's anxiety. I go back & forth on whether to see a doctor or not. The thing that keeps me from making an appointment is that I notice when I'm busy with something that keeps me focused, or really relaxed, these feelings go away. It was at its worst around Easter & then I read on here about derealization and depersonalization. I actually cried when I read about this because it described EXACTLY how I was feeling. Do a search for it on here!
Also, I have tight muscles in my back, neck, shoulders & chest, which comes & goes. (I have always gotten tightness in my neck when I'm stressed, which causes headaches for me.) Recently, I've been having soreness/tightness in my neck, jaw & ear area also. I'm wondering if I'm grinding my teeth again at night. (Apparently I cracked several teeth by doing this! I swear my inability to handle stress properly is going to pay my dentist's daughter's way through college!) I might get one of those mouth guard things to see if that helps & then see what my dentist says when I go back in a month. Is it possible that you grind your teeth at all?
Oh, and I think part of my ear issue might be seasonal allergies kicking in. They were clogged for a few days around Easter, then drained & since I've had some mild allergy stuff going on.
If your doctor keeps saying you're fine, you probably are. (And hopefully I am, too!) If anyone else has been through this, please share your experience!