You need to spend a lot more time in what I call trigger discipline. There are many ways you can do this, using a number of "tools", but time on the trigger, with your gun unloaded of course, is your best friend for conditioning yourself to eliminate flinch and shoot better.
Snap caps are great tools and the folks who recommend having a friend load your magazine with one intermixed with live rounds at a range is a great way to get the flinch out. But you need to get to that point first and that means trigger discipline at home. Try balancing a dime sideways on your front sight or if you have the OEM standard Glock sights, on the front of the slide. Then pull the trigger in your shooting stance. Do this until the dime doesn't move or fall off. Practice draw and fire. Strangely enough, people tend to flinch less in this exercise than when firing from a fixed stance, gun extended.
Make sure your action on your trigger is correct... this means you, not the trigger. Do you take up the slack in the first stage of the trigger (pre-travel) to the "wall" before actually firing the shot or do you pull the trigger from stage one to stage two all at the same time? Is your grip on the gun proper and firm? Are you concentrating on that front sight for your shot?
Trigger discipline is critical. I've been shooting handguns for 45 years and I still practice trigger discipline with my primary carry gun frequently. It's a skill I do not want to lose.
Personal opinion follows. As for laser sights, if this is to be a carry gun, I do not recommend the use of laser sights at all. In an extreme encounter you are not likely going to be in a position to activate them and even if you do, trying to get that red dot on your adversary is going to waste precious time. These are best left to the range or perhaps your home defense gun where you might have time. But for your EDC, I would avoid these sights. In their place, a good set of quality night sights would be the better move.