Just having thyroid test results that are within the so-called "normal" range is no guarantee that all is okay for you. The ranges are far too broad for that to be the case.
Please post your actual test results and reference ranges shown on the lab report so that members can assess.
My tsh fluctuates a lot and I have been to the ER countless times for tachycardia. Are you on a beta blocker? They help tremendously. If your tsh is fluctuating a lot like mine you could be having these symptoms even while they read normal. My doc told me that he believes I fluctuate between hypo and hyper so fast it is hard to always detect with testing (although we have caught it on some tests). I hope you find some relief! I am scheduled to meet with a surgeon to get my thyroid out.
beta blockers do work well with tachycardia. are they doing a Free T4 when they check? sometimes the proteins will stick to the cells and give a false reading. the free t4 test will separate the proteins from the cells to give a true reading. i usually have to remind them when i get my labs checked because i was getting a lot of false readings which led to being placed on wrong med doses.
i was diagnosed with thyroid cancer and had my right thyroid side removed. since then i havent had as many problems.