From the first set of pics it clearly looks like small male preflowers forming. I would wait a week and check again but i'm sorry to say I think its male.
Amber trichomes are DEGRADING thc, showing that they are past their peak THC content. Clear trichomes are IMMATURE and their THC content has not peaked. Milky trichomes are MATURE and their thc content is peak. Most growers aim for 30% amber and the rest milky, but as others have said you can...
Dude if you're in the UK theres no reason to have temp issues. Either your intake air isnt cold, or you're not venting properly. can you move the intake line to underneath a window (cold air falls)...
It's just algae caused by light hitting the perlite. Either cover it so the light does not hit the perlite or as others have said you can use a small amount of hydrogen peroxide to kill it. if left unattended algae can cause BIG PH swings.
A thousand ways to fuck up some newbies grow you mean.... OP: did you see my pics? this plant has been LST'd hard, every new stalk has been bent back down, ONE DIRECTION ONLY. Once it's bent down you just leave it and new stalks will sprout. The poster above also has the right idea with LST ^.