Can I go back to my previous surgeon to say I'm not happy?

Dear Friendly726622,
I understand your concern. However, without a proper assessment, it would be difficult to determine what went wrong. It is best that you visit your plastic surgeon for further assessment or ask for a second opinion. Only after a thorough examination, you can get proper recommendations and advice.
Daniel Barrett, MD
Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery

Go back to your surgeon and discuss your concerns. You might check your preop paperwork to see what is the practice's policy about revisional surgery and costs.

I am sorry to hear that your results are not in line with your desires. Some patients have very lax tissues and even though the proper procedure was done laxity returns. Sometimes as you pointed out a full lift was required to achieve your desires. A good place to start is with your surgeon to see what they think.
Do not be afraid to seek a second opinion.