I have a strange sensation on the tip of my tongue, it is notnumbness or tingling. I don't have any nutritional deficiency, my lab work was normal and I get regular allergy shots/medicines. What could be the cause of the strange sensation?

Good question? That's a very broad question and not easily answered over the internet without knowing your complete medical and dental history and being able to personally examine you. Honestly, merely giving you a list of possibilities is not helpful nor will it solve your dilemma. If no one has been able to answer your question, see an oral surgeon, dentist trained in oral medicine, or ENT specialist.
Burning tongue. Are you a smoker? Is your mouth dry? Is you acid reflux controlled? Sensitivity to food additives? Burning tongue is poorly understood and many times no treatment for this. Hope this helps.
Lack of taste buds. Does this always occur in the same place. Geographic tongue is often painless. There can be patches on the tongue where the taste buds are missing. It is a benign condition. Ask you dentist about this at your next appointment.