I agree with previous poster - a high percentage of new Glock shooters are low left...a ways, especially at that short of range. that said, Glock sights are notoriously 'cheap plastic' and often replaced. look at warren tactical's, dawson precision's, and heinie's sights - my unofficial guess at the most popular after market glock sight sets - I have had all of them , just recently got my warren tactical set from MLE shooting sports, $55, IIRC - free shiping on $100+ orders, so look around a bit - range bag, knife sharpening system, mag carrier..or more expensive sights.
there are commonly available cheapo- punches - metal with a plastic tip - I even got one free with one of my sight orders - don't remember who I orddered those from. I have changed Glock sights in and out several times with no damage to sights or slides. pop out the front sight, the replacements often screw in, and there is another cheapy (also got one free) tool do that with.