Hyperthyroidism/anxiety symptoms

I have a loved one who has numerous symptoms for hyperthyroidism (Excessive sweating, Heat intolerance, Increased bowel movements, Nervousness; agitation, Rapid heart rate, trouble sleeping, Decreased concentration, hormonal problems, etc) that have gotten worse with time. He has tested in the high range for T3 twice, than normal, than high again, than normal. Why 5 tests I don't know when the first 2 where positive. Now the doctor is insisting it is not hyperthyroid based solely on the last negative test. This is just crazy to me. Now he has to where a heart monitor for a month (this same doctor, well DO) diagnosed him with some heart condition based one occasion having a low heart rate (most of the time it's normal or is racing)-b/c he saw this condition before in family members. I think this guy is a quack, especially since he is good friends with my friend's parents and I feel this compromises his objectivity. He has the type of parents who don't want anything to ever be wrong so they manipulate EVERYTHING to appear that way even if it is not. I'm worried-he has asked for other tests and the doctor is stubborn and his parents insist he keep seeing this same doctor, even though he's 22. Does anyone else feel this is a valid diagnostic procedure??? Please help.

Thanks...any one else???