Yellow veins on seedling

Hello everyone, I'm just starting a few bag seeds for my first grow. I'm sure I'm doin a bunch wrong so don't beat me up to badly lol. So the problem is the main vain in the first set of actual leaves (not the round seed leaves) are turning yellow and I'm having trouble finding anything online deficiencies or toxicities that look like this. Any ideas I was thinking maybe ph but I don't have a ph tester yet so was hoping an experienced grower could help me save my babies b4 I wreck them w my inexperience. For all I know it's all good and I'm worried about nothing. Any input or suggestions greatly appericiated.
Here is a pic of the baby in question, and my little nursery(I know it's nothin special lol)

They look normal to me. If you have experience with plants in general. Figuring out how much water and how often is the most important thing to learn. Once you get that figured out the rest will be easier to figure out. Good luck.

I think the most important thing is providing enough light

Thank you guys very much. And I know the lights kinda shitty. Getting hps lights soon as I get paid. I'll keep doin what I'm doin thanks again guys

How bout that little hole in the right Hand leaf? It's deff not light burn,the light isn't strong enough to burn em from there so any other suggestions or is it something normal for these babies?

Here it is today looking worse!! Someone help!? There is deff. something going on here.