Haven't got a clue what's going on with the plant and I'm worried I've put in all this time for nothing.

There are 2 options: Not enough fertilizer or too much light, if you turn on the lamp at full power when the plant has not yet grown, it will simply be crushed by the light and the small plant will wither, you need to turn on the lamp at 30% when the plant is about a week old, after about 2 weeks you can increase the light to 50% and wait approximately 6-7 weeks until the plant forms buds.And only after this can you slightly increase the light intensity.It's about the light.But as I see on your plants there is a late stage of nitrogen deficiency.

Has been low on N for a very long time. React sooner. It's good to have patience and be certain of diagnosis, but this is too long. There's a lot of dogma out there and oversophisticated things you have to do at this point or that. the plant does have slightly different nutrient requirements at different life stages, but when the prescribed methods fail, it's time to drop those methods and make some common sense adjustments based on what you see. hopefully you tracked your fertilization methods - dosing/frequency. Make some adjustments to that plant for the future. It definitely needs more N but there may be other things out of balance too.

They look very underfed. yellow and browning margins on the leaves suggesting it needs N and K. What are you feeding them? and how often? whats the lighting schedule/DLI? PH, EC, do you have good air movement and got fans going? best to start a diary so others can see the information and give better feed back. a few pics with no history or stats is not ideal to troubleshoot the issues. I would not say they "look good" but they are not the worst things I have seen either. you need to do some work.

They look good keep it going. Might want to add in a water condioner like fish sh!t( its a product made in maine mixes in your wzter) really helps develop your terps. Patience is my real advice watch as your trichomes develop they go clear to cloudy to amber. Check grow diary articles for a guide. All in all though bud you will get there great job.

First off, not bad for your first grow! My first grow looked like a twig with hairs on it 😂 That looks like typical nutrient deficiency. Like humans, plants also need certain nutrients and minerals to survive. Soil usually gets depletes of all its resources after about 4 weeks and you'll need to transplant them -hence why transplanting into bigger pots is a thing some growers do- or feed them with supplements. The main nutrients are Nitrogen (N), Phosphorus (P) and Potassium (K). Hence the N-P-K feeding schematic. Have a look into this before your next run! And please, start a diary with your next grow :)

Don't get down everyone runs into problems. Spend some time evaluating your grow. identity your strengths and weaknesses and spend some time researching things to help your next grow. Manage expectations no one in their 1st few grows ends up following and curring and drying anything relatively near some legit gas. Be thankful your learning in todays world with infinite growing information online and with some nice leds and not hps or florecent Keep tring garentee by your 4th or 5th grow you will have it in the

Never think of it as failure, learn from your mistakes, there is no shame in learning. Whayeveryone else said, she look hungry for some nutrient loving.

Way under fed, or incorrect feeding............basically starving. Had you asked this question 3 weeks ago when the symptoms probably first appeared, there may have been a chance to remedy the situation. As it is now, the window of recovery is almost closed. Without a diary and/or a lot more information about what you have or have not been doing, the answers can only be guesses. These plants need feeding with potassium and phosphorous, aka a P/K booster. They probably also needs some supplemental nitrogen............however, letting it get this bad before asking for help may be too late to really "fix" anything much.

I agree with AsNoriu, all of these are heavily underfed so they are missing the building blocks to properly form cannabinoids and terpenes.

Do you see differences from yellow to green ??? Think they are heavily underfed.