I have burst a blood vessel in the middle finger of my right hand twice now in the same month. it starts out as an itchy feeling and ends up purple.

This is often: an elusive symptom. It actually tends to occur more in women and is sometimes associated with the connective tissue syndrome Raynaud's disease. This is a condition where small blood vessels constrict and may actually rupture such as you describe. It deserves a medical work-up to look for such conditions; you should carefully record the symptoms and circumstances and see your doctor. Good wishes:)