Is it possibled to MISS a diagnosis?

[AnxiousAndUnsure]

About 5 years ago I kept getting really sick with many many symptoms of a thyroid disorder (the only thing I've never had is a lump in my neck but I have everything else) I went to see an endocrinologist but she said my T4 levels were normal. I eventually started to feel kind of better but not completely. 5 Years pass and suddenly BAM I'm anxious/jittery/nervous for like NO reason. Even after a full night of sleep (if I can get one) I feel so tired. I'm fatigued and cloudy a lot of the time too. Depressed as well (for no real reason) and I'm unsure of why this is happening. There is another theory that it may be PMDD however it's getting worse and worse and farther away from my period (lasting longer than just the days I have my period). I also have IBS which can account for some of these symptoms, as well as GERD but it seems like I am just TOO sick for IBS and GERD to account for ALL of this. I'm wondering if it's possible for T4 levels to be normal during a test? I am also insanely underweight but I was told "oh that's just genetics" but that makes no sense because for a long period of time I was not underweight like this. For years and years I was 165 pounds then suddenly over a  years time I dropped down to 104 and since then it's been a huge struggle to maintain my weight but there was no logical sense for me to lose all that weight to begin with it just happened. I am seeing an endocrinologist on Friday (A different one for a second opinion) but are disorders like this missed commonly or is it an easy thing to check? I'm getting frustrated with feeling THIS SICK all the time and I don't have a mental illness history that would account for all these sudden weird symptoms.

[Red_Star]

Actually the documentary is "The Marketing of Madness: The Truth About Psychotropic Drugs." Also free to watch on youtube.

[Red_Star]

Youtube search: "Making a Killing: The Untold Story of Psychotropic Drugging" to watch the documentary for free.

[AnxiousAndUnsure]

How was it made up? I literally do not feel depressed/anxious the entire rest of the month ONLY on my period...if they can actually measure hormone levels (which they can) how is anyone making up PMDD? Also no one has ever suggested prozac to me to treat it, ever. Sounds like a conspiracy theory.

[Red_Star]

Thyroid conditions can be missed due to numerous factors. But to start with check your TSH, free T4 and free T3.

Btw, PMDD was made up in Eli Lily's marketing department since the Prozac patent was running out. They repackaged Prozac as Sarafem to treat this new made up disorder and spent 33 million to promote the drug. smh.