I have about 5 large cysts under the skin on my cheek. Just large red painful bumps under the skin. Today I woke up to notice the cysts have got the small white/yellow head on top of them.
I'm not sure what that means, does it mean all the bacteria is on its way out or does it mean its getting more sore or worse?
If anyone knows definitely let me know
Thanksss 
Looks like bacterial infection to me now when it got pus. Be careful not to drain the pus by yourself and don't squeeze it out it's contagious and can get spread to other places of your face. I'd say stop applying the tea tree oil, maybe it's undiluted and irritates your skin even more. You seriously need some antibiotics and a good bacteria killing gel, like Duac. I had very similar bumps in a very similar place and was immediately put on minocycline, but in my case I couldn't use it properly because of sensitive stomach, so my acne got out of control. Drink a lot too, try not to sleep on that side of your face, change your pillow cases daily and don't ever touch it with your fingers.
And don't panic, it's gonna be alright, just take care of it properly.
They are too Painful to even touch so I'm not going there, I'm going to come of the tea tree oil! I'm seeing my GP Wednesday so ill defo asked to be put back on anti and I'm receiving quinoderm soon which worked wonders for me! No way am gonna touch them, it's only that patch if skin so I can't let it go anywhere else!
Thanks for that x
By the way, have your tried putting a warm compress to it?
Here you can read a bit about it
http://www.skinacea.com/faq/acne/a03-how-to-get-rid-of-a-cyst.html#.UPSF--TFBLd