I wouldn't stress out about something like that! Just be sure to change your pillowcases 1-2 times a week like normal.You're much better off getting a good night sleep without worrying about turning over onto your pillow. When you have acne it's so easy to get OCD about every little thing, but most of the time it doesn't do anything except cause you more stress.

I've noticed that my acne worsen when I don't sleep on my back and that is why I try not to rub my face against the bed (Yes, I sleep without a pillow.) while sleeping. I've been doing this for the last couple of years and I am aware of how hard this is trust me. BTW sleeping on your back brings other health benefits.

As mentioned above, it could be, but if you change your pillow case once or twice a week, it should be fine. It's also good to turn it from time to time so you use the "clean" side. Having said that, some people are sensitive to cleaning products and break out as a reaction to the soap used to clean the pillow case or sheets. If you are worried you could buy organic washing machine liquid and try, to see if it makes a difference. Also white cotton pillow cases are recommended in these cases.

If you are not having a lot of issues with acne, I think you are fine.
Otherwise, I recommend you buy hypoallergenic bamboo pillows to help you get rid of your acne (or at least keep acne at a minimum level).
I had allergies and issues with acne, until I figured out the cotton pillows and sheets are the issue.
I bought bamboo pillows, bamboo sheets and even a bamboo mattress and since then I barely have acne.
To be honest, I never believed bamboo can make such a difference, but I'm really happy I gave bamboo a chance.
Definitely recommending, not going back to other materials. I no longer use acne creams either.
If you are looking for some ideas on which one to buy, you should read the amazon reviews or here is a site which reviews them: [Edited link out]