Sign of myasthenia gravis

I believe this is what I'm suffering from for a couple different reasons. I started noticing fatigue in my eyes in the afternoon last year at the beginning of the summer. This was followed by increased exhaustion after exercising that has now forced me to stop most of what I was doing. My Dad had to have open heart surgery at the end of the summer and I was having trouble getting a deep breathe periodically when I was dealing with anything concerning the surgery and chalked it up to stress about it and sympathy pains, kind of like how a husband may feel when his wife is pregnant. Fast forward to this summer and I am now on sick leave due to many more symptoms including worsening of breathing, double vision that seems to disappear when I only look through one eye at a time, throat muscles become sore as well as inside of my throat and I start to lose my voice if I'm talking more than usual, or am under stress and crying. The reason I am wondering if this is what's causing the issues is since my early 20's I had this funny symptom when I drank. My left eyelid is almost impossible to keep open more than a quarter of the way and it's a symptom that has gotten worse over the years. I have started to notice over the last couple of years that this happens when I'm very tired.. while not as severe as when drinking. I wonder if anyone else has noticed very early signs such as this before having signs that it's gotten bad enough to need treatment?
I'm becoming frustrated with my Drs who can't find anything on tests and keep asking if I am depressed or suggesting it's fibromyalgia and it's starting to take its toll on me.