I have been having this issue for a long time after grandfather's death in  2022.I got a blood test done at that time, it turned out to be a thyroid problem. I was having loss of concentration and overthinking. I took medicine and it got a little better but I used to feel a slight imbalance.  I used to have a lot of anxiety even when I was sitting in the class, that is why I got into the habit of shaking my legs, even when I was standing straight, I would keep shaking my legs without any reason.since then I felt like pressure and waves in neck area constantly specially while lying .When I comb my hair shoulders and arms get tired very quickly.I have recently had my gallbladder operation done after that I felt cold waves in my body. Now it has healed, I am feeling a burning sensation in my head for the last one or two days. I am feeling a burning sensation not only in my head but also in my arms. Now I am pressing my head and it is starting to burn. I start overthinking again as always.