What Causes Gnawing Burning Sensation In Abdomen, Nausea And Intermittent Constipation?

Question: It started with a gnawing and burning pain in the upper abdomen two months ago. Then mild nausea at times and on and off constipation. Lost my appetite completely for a week and felt very weak and tired all the time, and sleep wouldn't relieve the fatigue. Appetite and fatigue has gotten better lately. My pulse has slowly risen higher and higher during the last months and I'm now usually between 88 and 112. Had an episode where I was up in 160. I was positive it was a thyroid problem because my neck started feeling tighter and sometimes sore and I often get a sensation of a lump in my throat. Scarves and turtle necks feel uncomfortable on. I randomly get a hoarse voice and pressure on head and nose and my allergies have gotten worse. My doctor said that my thyroid was fine because of the tsh level of 2,64. I easily get cold and get chills often. My feet and hands feel cold all the time. Sometimes i feel like I have a fever, but my temperature is usually 36 degrees celsius. My pupils are often very dilated and wont keep constricted in bright light, they instead pulsate back and forth between dilated and constricted and I think because of this it is uncomfortable to look to the sides or up and down. My muscles seem weak and achy sometimes, and often twitch a lot. I recently most likely had a mild fecal impaction and was given movicol to empty myself. Still have a sensation of not being able to empty myself properly, but I am able to pass bowel movements.

Could this be a thyroid problem even though my tsh level is withing the normal range, or maybe a adrenal gland problem because of my pupils, or maybe both?