Can long walks right after buttock implant surgery cause seroma? 2 weeks p.o.

Its important that you follow your surgeons instructions carefully and NOT what you read on the internet of what you hear from friends. Its not recommended that you go on long walks after your procedure. Its recommended that you refrain from excessive physical activity for 4 weeks after your procedure. 

A seroma is a fluid collection beneath the skin.  Some times the patient just notices the area getting larger without any particular symptoms; seromas may cause a low-grade burning sensation in the area. Each surgeon has his/her favorite method of preventing seromas:  compression garments, use of surgical drainage tubes, or special internal suturing.It's always wise to follow your PS's post-operative protocols, and not those of someone else.  Schedule a post-op appointment with your PS.Kenneth Hughes, MD, Board Certified Plastic SurgeonLos Angeles, CA

Sounds as though you did indeed overexert yourself and likely now have a wound opening.  I strongly recommend you give a call to your surgeon today. Glad to help.