Don't start over. Separate the pots that have doubles (You might lose the transplanted ones). Just give them time bud, seriously. You have months to go on this grow still.
Hey I'm new at this so. I'm sure I'm doing everything wrong. So I have 5 autoflowers under some t5s and a vs1000 18 days old. Why are they so short? How can I lst?
The two cents of a first time grower, mine were pretty much that at 18 days and they came thru fine. Think I stunted mine a little with over watering, but different strains and phenos will do different things. Stay the course mate, use the forum these guys are gurus they will get you thru. If it's a watering issue you've got the best help already chatting to you on here so go forth! Excelsior!
The way I look at it is that I'd rather have three well potted plants and risk losing two (to transplanting) instead of having one well potted plant with four that are overcrowded and may run into all kinds of problems.
I honestly think you prolly have 2-3 weeks or more before flowering starts. Get the pots/plants situated the way you want and water them thoroughly. Then just let them be for a few days and monitor them.
Also, I would fully water those plants hard. It looks like there are cracks in the soil and the soil is pulling back from the edges which means it's really dry in areas not directly under the plant. Maybe it just looks that way though.
When growing auto's you should start them in their finish pot, They don't like to be transplanted. They only got about 4 weeks before they flower so you don't want to slow them down at all. Good luck and don't give up.