Most of your symptoms are also seen in cases of thyroid
disorders, iron defeciency anaemia
or hypoglycemia(low sugar levels). I would suggest that you get your Blood sugars (Fasting and post prandial blood sugars) and Hb level checked.Has an ultrasound
of the thyroid been done? Probably you are feeling tired the whole day because you are unable to sleep at night. It could be due to sleep deprivation
The nodule under the jaw and on the back of your neck also needs to be evaluated .
Are you going through any stressful situation? Are you on any long term medication? You definitely need to visit your physician to be thoroughly evaluated. In the meantime,try to relax. Have a nice shower in the evening . Listen to soothing relaxing music, or read a book. Join for meditation
classes to help you relax. Avoid having coffee late in the evening or night. It will keep you awake and you will not be able to sleep.
Please visit you doctor at the earliest. Get well soon :)