I'm pregnant and was just diagnosed with puppps. What could happen now?

Varies. Some people tolerate puppp with no treatment. When needed, the most effective treatment seems to be systemic steroids. See your doctor.
PUPPS. I'm going to start off by saying that pupps is treatable...Not curable. Most doctors will give you steroid shots or medicated creams to relieve the itching but this pregnancy rash will stay with you until you have had your baby. There are a few women who have reported getting pupps after the birth of their child but this is extremely rare.
No risk to the baby. There are several rashes associated with pregnancy. Some types are high risk to the baby, but puppps has no risk to your baby. The discomfort of itching can sometimes be lessened with over the counter creams such as benadryl, (diphenhydramine) hydrocortisone, or calamine. Mild soaps such as basis may also be helpful. Your doctor may also recommend an antihistamine. Puppps resolves after delivery.