Arrows shot through lava or fire and onto TNT repeat animation forever

When I shot an arrow downward through lava, the arrow struck a block of TNT. The TNT lit and detonated, but the arrow fell down and then teleported to where it hit the lava and repeatedly fell over and over again. I tested this with multiple other setups (shooting from the side) and the arrows would always repeat their shooting animation after hitting the TNT and detonating it.