Constant Tiredness, Nausea, Lightheadedness, Chills, Mood Swings, Headaches, Eases On Eating, On Coil, Feeling Of Knot In Stomach. Cause?

Hi I m feeling constantly tired, nausea , light headed, dizziness , shivery, even tho hot , and very emotional , headaches , and randomly enough comfort eating, I thought pregnancy to begin with but have had coil fitted for nearly 4 yrs now even tho breasts are very tender right now . Also the other day I bent down only to get what is described as a solid knot feeling in the lower right side of my stomach pain was unreal I was bent over and couldn t move as my stomach felt locked up any advice for me please thank u !!!