Thanks for query,
you have first loss of weight, then Protruding eye ball,Malaise,Easy fatigue
occurs along with symptoms then you should diagnosed as having Hyperthyroidism.
Your blood report also confirms that you have no hyper thyroid.
as your EKG has normal tracing it is a simple Tachycardia may be due to anxiety
so you continue with Beta blockers.
Don't forget to go for periodic EKG tracing to watch for any disturbances in Rytham.