Hello,
From your symptoms adult acne is an important possibility to be ruled out. You can also treat acne by cleaning your face regularly, using skincare products, apply antibacterial topical medications. With the help of the doctor, the treatment of oral antibiotics, contraceptive pills, retinoids, cortisone injections, chemical peels and laser treatment can be your choices.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
Probably caused by a change of diet. Watch closely and mark the things you eat. If it gets better or worse you will find the foods or drink that is causing it.