Engine pops at high revs

89 s-10, 133000 miles. 4cyl 2wd. I accidentally shifted into 2nd when it should have been in 3rd and revved the engine really high. Now the engine pops at higher revs (about halfway through the gear until i shift). I was told this might be a timing issue. Also my water temp light comes on very dim at first then gets brighter the longer i drive, i changed the thermostat and the temp sensor but the problem still exist. Any info on these 2 problems would be greatly appreciated
Thanks
Tony