Have you been using any new makeup or facial products (cleansers, etc)? You could be allergic to anything, and if you like to try lots of new products it will be really hard to narrow it down. (Whereas I wear the same foundation, powder, concealor, and acne medications every day -- and when I try something new, it's only one new product, so it's easy to see if I have a reaction.) Also keep in mind that some oil-free products can still contain ingredients that can clog your pores; products labeled "noncomedogenic" or "nonacnegenic" will be even less likely to clog pores -- if you do have clogged pores or acne as opposed to an allergic reaction. Also remember that stress can cause acne, I tend to break out during exams week! lol
If it doesn't go away you can always see a dermatologist, and he could probably tell you at least whether it's acne or a reaction and some tips to help get rid of it. (When I was in high school, my brother and I went to the dermatologist together and he looked at us each for about 60 seconds and said I had oily skin and clogged pores, while my brother had "true" acne, and he gave us each different medications and prescriptions!)
I've collected a lot of tips from my dermatologist about things to do if it really is acne or clogged pores caused by oily skin:
- Changing pillowcases at least weekly as lizzy mentioned, and also changing your washcloths and face towels at least every other day.
- Many shampoos can clog your pores, since it's easy to get shampoo on your face in the shower. My dermatologist gave me a list of "safe" shampoos, the only ones I remember are Herbal Essence and Prell.
- All conditioners have pore-clogging oils, so only use conditioner on the ends of your hair so it won't get on your face (this helps prevent your hair from getting weighted down too
)
- If you have really oily skin you don't need to moisturize it (I know some disagree but some dermatologists say no moisturizing), and if you do moisturize make sure it's a noncomedogenic moisturizer like Cetaphil.
- While eating certain foods has not been proven to cause acne, if you eat greasy food and then touch your face with greasy fingers that can clog pores. My dermatologist recommended washing my face after every time I ate greasy or fried foods (like I'm going to wash my face and redo my makeup after lunch....)
- Exfoliation can help prevent clogged pores. My dermatologist recommended using Cetaphil bar soap (or Dove if you want something more moisturizing) with a Buf Puf brand sponge to cleanse and exfoliate at once.
I know Janelle mentioned prescription Differin gel; that worked ok for me but after using it for a year or so my dermatologist switched medications. I was using Clindagel in the morning and Tazorac at night and it was working really well.... but now I've been using OTC products to save money but I haven't found any that work as good so I may break down and go back to the prescriptions. Right now I'm still using the Cetaphil soap and sponge at night, plus Biore Shine Control Foaming Cleanser in the morning (doesn't seem to help the shine so I probably won't repurchase), Stridex Maximum Strength twice a day (2% salicyclic acid, a common acne medication), and I just started using Neutrogenia Spot Treatment at night which contains 2.5% benzoyl peroxide -- most creams contain 10% benzoyl peroxide but that can dry and irritate your skin, while the 2.5% seems to heal the acne without drying my skin, I've noticed quite a difference after only 2 weeks! (And pores clog 2-3 weeks before you see the acne so it usually takes a while to notice a difference with a new product!)
Anyways that's about all I know on the matter, hopefully it will get better soon or a doctor can tell you what's going on!