it's early, if healthy otherwise, power through it.
if you took note of all you have done so far, try somethign slightly differently next time, but could just be inevitable too.
lots of things can cause that. but, if oyu haven't doused it with overfertilization, it could be many things out of your control, too. I see it often on young plants. I assume it's environmentally related when all other things are dialed in and plant looks healthy otherwise. e.g. heat can cause that, i'm fairly sure.
Now in a week or two it is still popping out leaves that are all curly, you may have to worry.