Hey!
You got yourself some leaf miners.
These little bugs are larva that are eating your leaves from the inside out, when they get big enough they break through and leave..
That normally results in your little baby cannabis plant getting very damaged.
Luckly they can be easily found with the traces they leave behind.
So what can you do about?
You can first wait and check if they're actually leaf miners, if they are those little lines with get longer by day..
If that's the case...
1. Cut off all of the infected leaves.
2. Use a cannabis friendly pesticide, Spinosad work good and are organic if not something similar.
That should do the trick.
Hope this helped.
Good luck and happy growing.