It depends how bad it is. Vagin.al tissue is designed to be torn a bit though - its a similar structure to the cells in your cheeks which have to deal with teeth. There are layers and layers of cells of which the top layers come off frequently. This is perfectly normal and wont cause any damage. However, it shouldnt cause bleeding, or pain. If that happens you might want to be a bit more gentle. If it takes a while to heal you should see a doctor.
it really depends what tissue. naturally some tissue will tear and thats okay but if it is painful/bleeds it should probably get checked out by a doctor. gooodluck :)
it can be, it could cause an infection and if the infection doesnt heal or gets worse, then it can end up doing damage
First time vaginal sex? If so it is pretty normal- if there is continued pain or bleeding best to see a doc.