Yellow spots on seedlings

Noticing some yellow spots developing and some slight up curling of leaves on one of my seedlings. Does anyone have any ideas? And should I be concerned at this point?

Did some research and I’m thinking it could be from PH swing. I’ll have to check my PH when i water tomorrow and monitor the results. Also I’m thinking that the curling upwards of the leaves could be heat stress. I raised my light up a couple inches. So over the next day or two ill monitor the leaves and the min max temps i the tent.