My middle finger tip on my left arm has felt numb and has a tingling sensation for the past couple days, any idea why? or am i just crazy?

Numbness: any history of trauma? Previous history? Occupation? Most likely inflammation of median nerve or its root. Could be mild carpal tunnel. Take some anti inflammatories and see if that helps.

Where is the lesion?: If its just the middle fingertip you probably squeezed something too hard and have an issue with what's called a proper digital nerve. Recovery depends on weather or not the injury caused focal demyelination or actual nerve injury. (Usually the former takes a week or two and the later may take months if the nerve has to regrow. Sometimes Carpal Tunnel or a pinched nerve in the neck can do this

Digital nerve: Likely a problem with the smaller nerves on your finger, and should resolve over a few days, but could also be due to early carpal tunnel syndrome. Your doctor should be seen if persists or worsens over next week or two.