Our own galaxy is on a collision course with Andromeda. Will it hurt?
No, the stars (and planets orbiting) residing in each galaxy are too far from each other to collide or really interact in any way. Perhaps in the inner regions of the galaxies (around the central nucleus) some may disturb one another to a great extent, but out were Sol resides between spiral arms there is no danger from collisions. Only the interstellar dust and gas from both galaxies would collide, resulting in some spectacular light-works or even nova. This would take place over thousands of years.
Define "hurt". The galaxies themselves will be shredded by gravitational interactions before recoalescing into an elliptical, but the individual stars and planets will mostly survive intact. There will be a huge burst of star formation that will increase the chances of being in close proximity when supernovae take place, and some star systems may be ejected into intergalactic space (Which would be a lousy place for a civilization to find itself, bad enough when stars are "just" a few light-years apart, try interstellar travel when the nearest star is hundreds of light-years away.), some might get thrown into the central supermassive black holes at the center of each galaxy. Infalling material will trigger a quasar outburst from the central sbh which would fry any systems in the path of the jets. As far as Humanity and Earth goes, the Sun will be its death throes by then so it's a moot point anyway. Either we have the technology to avoid danger or we'll be long, long extinct.
Recent data suggests that the Milky way is more massive than Andromeda, which previously(to my knowledge) it had been Milky way was larger while Andromeda was more massive. Collisions between stars are extremely unlikely, though is possible over timelines which are longer than the life of our star. And obviously the super-massive black-holes will eventually collide. Some simulations show we will become an elliptical galaxy whiles others show we will remain a disk galaxy with new arms and trails as some systems are thrown either out of the galaxy system(s) or thrown on extreme elliptical orbits extending out towards the equivalent of a galactic "ort cloud" before beginning their journey back.