they seem a bit stretchy: lack of light
a bit light green: soil may be poor in nitrogen
a tad bit smaller than what i experience with mine after 2 weeks.
i wouldn't bother much about twisting as it happen pretty often when you grow large amount of plant one show similar twist as yours when all the others don't. So most prolly that's just the phenotype.
So yup may be the soil. But as you can't say for sure.