Preflowering concerns....

My plant has had preflowers for a couple of weeks now (maybe she'll be flowering soon, i dont know when to tell if she's into full flowering, maybe you can help?) and i have noticed that the older preflowers, and some of the newer have already had there white hairs turn an amber/redbrown color? Some of the preflowers seem to be getting a yellowish tinge too,, but that has only happened at those preflowers further down on the plant. all of the new growth is green and has white hairs. Is this normal? Is it normal for some to change color so early? or is this just something preflowers do?

Also one last question, is it normal for leaves at the bottom of the plant to turn yellow and wilt away? I have found this happening on my female plant alogn with my others and was wondering if its normal? I'll get a pic up of the plants tomorrow maybe, or next week. Thanks again!

Yes it is normal for the older pistels to turn amber/brown and wither and it is also normal for the lower leaves to turn yellow and die. Just make sure the yellow doesn't start speading upwards.