Are these 11 day autos too small

First, your plants look healthy... And that is the biggest thing to be worried about. you could try a light dose of nutes, but i'd wait for cotyledons to show a little fade first. Once the larger leaves pop out, it'll hit warp speed in no time. bigger the canopy, faster the growth (+ unseed root expansion, of course) stick to a good wet-dry cycle and she'll be great. allow top 1/2" to 1" to dry before watering with a bit of runoff.