I have a spot between two molars that randomly started hurting (a dull ache, no sharp pain) last night while brushing my teeth. It also bled a little. It only happens when I brush my teeth, so I'm fine while eating and drinking. No heightened sensitivity. I'm also a grinder, but it didn't happen yesterday morning. I did use a different toothpaste yesterday morning, but it is one I have used before. I'm unemployed and uninsured and cannot afford to see a dentist.