Stunted seedling; will it catch up?

Hey guys, just looking for some insight again. I have moved both of my seedlings under a 430w HPS lamp and they seem to be growing MUCH faster than when I had them under the shitty reading lamp before But, when I was moving one of the plants to a different container, I damaged the stem a little bit. I let the stem rest with some toothpicks and twist ties and I also used a fan to help encourage stem growth. It now supports itself fine but it seems to have much less space between its sets of leaves compared to my other plant that did not have these complications. Please let me know if you think it will continue to be a "runt" and will be smaller for the rest of the grow or if there's something that I can do to help it along. If it will be smaller for the rest of the grow, is there anything that will complicate things further down the road or will it just yield less? Also, I have the light on for 18 hours a day using a timer, should I put the fan on with the same timer or should I have the fan going 24 hours a day? Thanks for the insight guys; take it easy.

The one I'm worried about is in the second picture.

Bumpy bump for insight

well, they look streached a little bit... i imagine its cause of the "reading lamp" you were using, im guessing it was a incadesent bulb, by the stretch?...but, other than that, the stress you made from damaging the stem could have stunted growth on the one plant, and with good conditions it should coutinue regular growth in no time..or its just a different pheno, probabaly more indica dominant..

Alright thanks for the reassurance bro, so with time it should catch up? I'll wait a while and see if it gets better.

EDIT: Or, it could be different genetics that are just predisposing it to be shorter right?