Symptoms of a neurological disorder

Given the data you provided, it seems likely that the sensation of “a very hot water drop trickling down the skin and cooling down as it runs” is simply a nerve sensation (we can not feel our blood passing through veins). Although not so typical one, paresthesia (tingling/trickling) might appear as a symptom of a cervical spondylosis (degenerative osteoarthritis of the spinal vertebrae and related tissue), due to working in front of a computer, as one of the examples.

To prove or exclude this in order to prescribe treatment, your family doctor might want to do an X-ray of your neck spine. This might also turn out to be a condition called erythromelalgia (periods of burning pain, redness and warmth in the feet and hands), although it is very rare. Moreover, in order to exclude more serious spinal cord disorders, a spinal MRI could be done, as well.

Only if all organic causes are excluded, it could be presumed that there is a psychological cause, so both appropriate oral treatments accompanied by behavioural psychotherapy might be prescribed. Meanwhile, it could be wise to take vitamins from the B-complex group, such as vitamin B6, B12, B1, etc., which are good “refreshing” for our nerves.

As for the bruising, many factors could be the cause, and one of the first basic diagnostic tests that your doctor might choose to do are CBC-complete blood count (with leukocyte differential and thrombocytes-platelets), together with hemostasis tests, such as PT, aPTT, etc., as well as the simple Rumple-Leed test of blood vessel walls, all for discovery of the right cause of the easily-provoked bruises. Meanwhile, you could try to strengthen the capillary walls with regular oral Vitamin C of 1 gram dosage, on a daily basis.