Hi @Matt308 and welcome to OG
It’s really hard to tell from these pic and with limited information but this certainly could be caused by overwatering. One sign I am not seeing is dropping which almost always accompanies overwatering. Your soil looks very wet in the pictures so either way I would let that dry out somewhat before watering again. Other common issues that would cause this sort of damage are:
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Nute Burn - what type and strength of nutes are you feeding? Baby plants don’t need much so even small amounts can damage them
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Water or Soil PH - this one comes up all the time. What’s your waters PH? How do you test it(how accurate is your meter)? What is your run off PH? Have you done a soil slurry test?
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Root problems - I notice you are growing in styrofoam cups, how is the drainage? There should be lots of holes in the bottom for water to drain. Can you re-pot in slightly larger container with better drainage? This would also offer you a chance to check your roots visually.
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environmental- how far are your lights from the plants? How high are the lights set? is it too hot or cold in your room? Does the temp drop dramatically at lights out? What is your humidity?
look at all of these areas and I’m sure you plants will be bouncing back in no time. This biggest part is don’t give up, they can almost always be salvaged for a good harvest.
Cheers,
Loggershands
i would say so, but maybe nute burn?
@George makes a point with potassium deficiency. While overwatering can cause all sorts of strange deficiencies to show up, there’s usually tell-tale leaf droop—and potassium usually isn’t the first deficiency to show up from overwatering.
The most common causes of potassium deficiency, assuming you’re using some nutrients, are lack of aeration/drainage causing root issues and high pH due to bad pH calibration or not using a pH meter at all.
More details would help, such as what sort of soil you’re using, how much & how frequently you’re watering, what nutrients (if any) you’re using and how much/often, pH of your water/nutrient solution, etc.
Hi and thank you for your input, I’m using ph meter and calibration has been done recently, I have yet to use any nutrients, I’m using pro mix organic soil…iv orderd some ph down as I can’t get it in my town, iv been watering with tap water that’s about 6.7ph…I only water when they feel light/dry my humidity was little low for a while but I have it about 60% lately…Temps about 80…
You can use some 
juice drops to lower pH. Trim those scorched lower leaves, they can be a gate for mould.
With that settings you should be fine, maybe you’ve got a root problem 
, do you have drain holes? Is soil very compacted? Does it have perlite?
New growth looks better, if you see later on problems going upwards I would blame it on roots … 
Is this the soil you’re using? If not, could you kindly post a link to what you’re using?
If you’re using what I linked, there’s typically only a starter nutrient charge that allows plants to get about as big as yours before they need nutrients. It’s intended to be used with compost or other plant food/nutrients through the growing season.
Do you have a plant nursery or garden store around? Even the garden section of Walmart should have a semi-decent supply of plant food.
They’ll usually sell a basic 10-10-10 fertilizer that’ll get your plants into a better state. I’ve seen people have good results with simple stuff like that. Long term I’d look into the Jack’s 321 program (search for several good threads).