Is this anxiety or am I missing something?

I definitely suggest speaking to a doctor like you said you're going to do, but with that said: when I've had my episodes of panic attacks, those are the symptoms I've had - lump in the throat almost like I can't swallow, sweaty palms, heart palpitations, headaches, hyperventilation - the first time I thought I was having a heart attack (I have a diagnosed anxiety disorder for which, unfortunately, medications don't help but luckily I don't have episodes often).

The problem with it, though, is those symptoms can come from a variety of potentially life threatening things and the only one who can rule those things out is a doctor.

Today my morning sugar was normal (87), blood pressure was normal (123/72), thyroid (1.4) and electrolytes were ruled out in tests from last week.

Yesterday I was fine, but around 9a this morning I had what I think was a bout of anxiety that lasted about an hour or so. Only some of the original symptoms occurred: lump in throat, cold hands, sweaty palms, very slight shakiness. :ohwell:
In your opinion, am I experiencing anxiety unrelated to the above or am I missing something?

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(I do have a doctor's appointment scheduled for tomorrow morning.)

Did your doctor do a full thyroid panel, or just a TSH? Thyroid Stimulating Hormone is actually a pituitary hormone that signals the thyroid, not a measurement of thyroid function. Just because TSH is normal or low, doesn't mean you're making enough thyroid hormone, or have the right balance of T3 and T4. It can also mean your pituitary gland isn't putting out a strong enough signal to your thyroid to produce hormones.

Not a doctor, just giving you a possibility to check into.

I was diagnosed with a panic disorder several years ago after suffering from upwards of 30 panic attacks a day and being in a heightened state of anxiety 24/7. My symptons led to a feeling of going cold all over, palpitations, tearful, body aches and a feeling of constant dread. When an attack happened there was nothing I could do except wait it out and usually that required me to leave the area. I now have medication which controls the main symptoms.

My GP suspects I don't produce enough serotonin which in turn generates the anxiety. I haven't always been anxious so it's fairly obvious that something changed and a few things I've learned suggest that the foods I eat (or, in my case don't) have an impact. Foods that are higher in Tryptophan appear to boost serotonin:

Dairy products such as cottage cheese, cheese and milk, soy products such as soy milk, tofu and soybean nuts, seafood, meats, poultry, whole grains, beans, rice, hummus, lentils, hazelnuts, peanuts, Eggs, sesame seeds and sunflower seeds.

I am vegetarian and had cut out most dairy products/carbs (to lower my fat intake). Since bringing dairy and carbs back I rarely have anxiety and, ironically, my weight loss has become easier. I sleep better, look better and am generally more balanced.