Dr. Mills graduated from the University of Florida with a Bachelor of Science degree in Microbiology. In 1990, he graduated from the College of Veterinary Medicine at the University of Florida with a Doctor of Veterinary Medicine degree.

He completed two preceptor externships at the Animal Medical Center in New York City and at the California Animal Hospital in Los Angeles, California. He gained experience in emergency medicine, neurosurgery, and orthopedic surgery at the Animal Medical Center.

The doctor furthered his surgical experience in a surgical referral practice at California Animal Hospital. He then completed a formal internship in Hollywood, Florida, at Hollywood Animal Hospital in general medicine, surgery, and emergency medicine. Since 1991, Dr. Mills has been practicing at Pasadena Veterinary Hospital. In 1999, Dr. Mills was trained in laser surgery, which he has practiced ever since.

Dr. Mills is very active in the local and national veterinary community. He has served as the president and a member of the board of directors for the Pinellas County Veterinary Medical Society and the Pinellas Animal Foundation. Dr. Mills is a founding member of the Pinellas Pet Partners. He was a television host of the series Pet Improvement and appeared as the guest veterinarian on Fox™ Channel 13 news. He has also served on the board of directors for the Florida Veterinary Medical Association, where he was honored with the Gold Star award for outstanding contributions to veterinary medicine.

Dr. Mills is a past president of the alumni council of the University of Florida's College of Veterinary Medicine and the Pinellas County Veterinary Medical Association. He is also a member of the American Veterinary Medical Association, American Animal Hospital Association, Florida Veterinary Medical Association, Pinellas County Veterinary Medical Association, and the Pinellas Animal Foundation. Dr. Mills' pet family includes a miniature Australian Shepherd named Fergie, three cats named Hangaberg, Princess Leia, and Ti Chi, rabbits named Tootsie Pop, Daisy and Butterscotch, a Albino Indian Ring-neck Parakett named Moe, and the newest member a Beagle dog named Brandi.