I have been feeling fine on 50mcg of levothyroxine until now. I'm on my 4th or 5th week, I take my tablet first thing in the morning then come evening time I get a racing heart, I feel hot, I feel hyper, my ears are ringing and I feel like my words are slurring because I'm talking so fast. I also can't think straight. Do you think I should half my dosage. I can't see my dr because of bank holiday now. I'm actually considering going to a & e tonight I feel awful.