Heart palpitations can be from many many things. However I found they are usually from 1)dehydration 2)adrenal problems 3)mineral deficiencies 4)low blood pressure. Most people assume they are not dehydrated, but don't always assume this. There is a condition (diabetes insipidus) where you drink lots and lots of water, but are chronically in a dehydrated state. You may or may not know you have it because the associated behaviors become "normal" for you. Even Dr. Cutler talks about mercury toxic people with partial diabetes insipidus because mercury settles in the pituitary gland. Adrenals are the big one and almost everyone has some adrenal fatigue. Lastly I find potassium and magnesium deficiencies affect the heart and other muscles. The fact you have other numbness and tingling it is probably a combination of mineral deficiencies. Low blood pressure is usually a complication of adrenal fatigue, but it is also seen in dehydration too.

My left leg from the top of my knee to my hip was completely numb. It was sooo bothersome. What I did was get 1 b-12 shots a week until the numbness went away. Now I just get a maintenance shot whenever my fingers start to get numb and it goes away in a few hours. B-12 pills, sublingual tabs and patches did absolutely nothing for me. So if you've used those and it didn't help you, don't rule out a shot.