1st Grow, Need some advice plz!!

Hey everyone. This is my first grow, I have a few concerns that I was hoping some people here could help me with.

About 2 weeks ago the fan leaves on my plant started to turn yellow...and eventually turned brown sometimes at the tips and sometimes in spots, dried up and fell off. It seemed to start from the bottom, and seems to be working its way up and now most of my fan leaves are yellowing and starting to turn brown, dry up and then fall off when barely touched. I was told that sometimes this is normal when the plant is in its later stages of its life cycle, which mine is... I know my plant is a few weeks away from being ready to harvest because about 1/3 of the pistils have turned amber. My question is this, does this sound normal to you veteran growers or should I be alarmed??

I was told that I should harvest when about 70-80% of the pistils have turned amber... Is that correct?? I don't have a microscope to view the trichomes but I would like to know whens to best time to harvest.

Thanks in advance to anyone who can offer a little friendly advice

yeah its perfectly normal for the bottom leaves to turn yellow and fall off as long as its not like half way up your plant your fine on mine the 2 little leaves the plant starts off with came off and then the first level of fan leaves.
im not sure about when to harvest though because this is only my first grow and im only in my first week of the flowering cycle

its normal to yellow, they don't fall off and get spotty or brown and dead though, what you are referring to is over fertilization.

if you can't afford the 10 bucks to get a pocket microscope from radio shack, or order one online then i don't think your really serious about growing. you will just have to guess when its done.

good luck.

Well I haven't used any nutes.. but some miracle grow potting soil was added(about 3-4 weeks ago) to the pot my plant is in.... would that be causing the nute burn???

my plant is getting close to being ready(within a few weeks) to harvest and thats why im trying to find out what the problem is, incase I need to harvest early..

OH snap, i dunno but i heard that miracle grow destroys that green bitch

well naw man it aint nute burn thats what happenes during the flower stage the plant takes up all the nutes and energy from the leafs to throw into ur buds and yeah go to radioshack and buy a 420 microscope real cheap