Yes. But remove the piercing first.
Yes. Likely yes, but with the piercing out.
Possible infection. May be sign of infection. See a doctor for possible cultures and to prescribe an antibiotic after evaluation.
Not really. If they've been pierced recently it is best to allow 1-2 weeks for the piercing tract to heal before exposure to potential sources of infection. Salt water would be less worrisome than fresh water swimming but either can be a source of irritation and/or infection. Once the piercings have healed swimming should have no effect and is fine.
Infection. See a doctor to evaluate for possible infection, cultures and to prescribe antibiotics.
Yup - genital. Piercings often do. A number of potential problems can occur when women have genital (to include clitoral) piercings. Jewelry worn through the piercings may cause condoms to break during sexual intercourse & for diaphragms to become displaced. There is risk of bleeding, allergic reactions (especially with any nickel content in jewelry), scarring (to include Keloids) and infections.
Difficult. It will make it difficult for the baby to latch onto the breast and produce adequate breast milk. If you want to breast feed which is great, wait for the nipple ring. It also may cause trauma or misshape your baby's mouth. All the best.
See doctor. Some mild redness around a piercing site could be normal but only an examination by a medical professional can determine if you really have an infection. If infected, you'll probably need antibiotics in addition to good hygiene of the area.
Usually not. If the person is clean, there's no reason one would contract a disease from licking the nipple.
Doctor. Best to have an examination to determine if there is any infection. You could go to your primary care provider, urgent care, or even an emergency department if you think it can't wait for a regular appointment.
Surgeon. I recommend you contact your primary doctor and ask for a referral to a breast or general surgeon. You should be evaluated for an infection.
Could be milk. Some of my patients with pierced nipples have a milk discharge (called galactorrhea). Chronic stimulation of the nipple (from the ring or bar) can cause lactation, even when not pregnant.
Pierced nipple. Pierced nipple = body piercing at base of nipple.