Those little bumps on the back of your tongue are more than likely circumvallate papillae. This is something I have only looked up for the first time since reading your post, so you may want to check my facts. From what I have read, everyone has these and they are quite small, 1-2mm in diameter. Some health conditions can cause them to swell, such as throat colds, dietary changes, and even allergies. They usually look dome-shaped or like truncated cones. After looking at mine in the mirror, I can at least confirm that
More than likely that is all they are, but you should pay a visit to your family doctor or dentist just to make sure.
The thing about oral HPV and cancer is that it takes years of persistent infection to develop. Regarding oral warts, while they are very uncommon, they can form, but that typically only happens on the lips and front part of the tongue. Chances are what you have are natural lumps that have gotten irritated, but again you may require the help of your doctor to confirm this.