I noticed a small hard red bump on the roof of my mouth abt two yrs ago. Now I suddenly have another one. What could this be and should I be worried?

Torus. Hard lumps in the roof of the hard part of the palate are usually a congenital and normal variant called torus palatinus(bull's palate) and requires no treatment. An otolaryngologist is best qualified to evaluate and advise you if you have further concerns or if the lumps are in the soft part of the palate.