How common is a reoccurring pid after just being treated for one less than two months ago? as well as two yeast infections in a month? was treated with antibiotics for pid, now a few weeks later the symptoms are back.

Very common: ...if you are not practicing safe sex (using condoms as protection) because if your sexual partner(s) have the bacteria, they may continue to transmit it to you and you can keep getting re-infected. Yeast infections are not sexually transmitted and can occur due to increased moisture in/around the vagina and due to changes in the vaginal pH.