I've just got PRP + ACell, is it possible to see results in three months?

You need to see your doctor for realistic expectations. Just because you had a PRP or Acell treatment does not mean you automatically see results.  

I combine with progresterone I find you get better results and I tell everyone they need to wait 4-6 months to see improvement.  If you see none at that time then abandon the treatment.

We don't have enough data to support the long term effects of PRP and Acell for had restoration purposes.  About the onset of growth if any, I think you have to discuss it with your doctor and see what he has to say based on his previous experience.

There is no scientific studies that prove that these treatments can improve genetic pattern hair loss. Mid there is any improvement it is very temporary and treatment needs to be repeated every couple of months. It is best to see a hair restoration specialist to find better treatment options to meet your needs and expectations. 

PRP can show results in that period of time making the hair fuller by stimulating its growth. The hair cycle is about three months.