New grower- 4 weeks old plant, leaves drying out

Hi everyone,
I am a new grower. This is my 4 weeks old cannabis plant. The strain is white ice feminised, which is mainly indica, and I am growing indoors in a grow tent. I am using a 240w cfl lamp with 6400k for the vegetative stage. The lamp is about 11 inches above the plant. I am growing in soil that I got from a gardener's shop and I ve been watering the plant taking care of its ph. I ve used nutrients 3 times but within 2 weeks time. I am also using a humidifier to keep the humidity on a higher level and a small fan since the climate is quite hot at the moment where I live. The temperature in the growtent ranges from 28-32 Celsius ( 82-90 Fahrenheit).

Last weeks I noticed the tip of my leaves drying out taking a brown colour and now it has started to spread all over the leaves and I also spotted some brown spots on the newer leaves. I don't know what's wrong with my plant. Do you think it could be nutrient burn, light stress or maybe heat stress?
I ve also sprayed the plant with neem oil in order to prevent the spider mites getting on my plants( I had a some spider mites on my other plants I ve got in my balcony). Do you think that neem oil might have done the damage?
i would very much appreciated your help since this is my first grow and I am getting stressed that my plant might die if I don't take action. I ve attached photos for a better idea of the condition of my pplant thank you very much in advance

Leave it alone...the plant looks healthy enough at this stage...probably a little neem issue but the plant looks fine IMO

Thank you!

Lower your temperature. 82-90 is way hot, if you have dry heat then add a cheap Swamp cooler if AC and electricity cost is an issue. You can leave it alone but if it's spreading even more, leaving it alone and ignoring the issue could only worsen the situation. LOWER YOUR TEMP. What nutes are you adding, What kindda soil are you using? You control the PH at what level?? That soi looks like it could use more perlite just from the pic, not sure how the drainage is.

Thank you,as well,for your reply!!!!

Temperature will get cooler by the end of September where I live. I have a fan inside the tent but doesn't do much!!!!maybe I need to find another way to keep the tent cooler but I don't have AC on the room where I keep the tent. Maybe wait for the outdoors breeze that i can get through the balcony door or get a cheap cooler as you say sheldonblack
My soil is an organic soil for vegetables mixed with perlite and pumice stones at the bottom of the pot. I am using bio-grow of bio-fizz as nutrient.
The tap water,I am using,is 7.5 ph. I reduce it to 6.5ph but after I water the plant the water that comes out on the tray is 6.0 ph. Maybe I need to water it with a higher ph to even the difference with the roots ph...

Loving it is doing it good,they say.... I am certain of my emotions