Whatever your definition of sloshing is, this would not be considered normal at 13 weeks. Early on this finding suggests air of fluid around the implants, but the air should be absorbed within 7-10 days, fluid should certainly be gone by now.
No one will be able to diagnose this on line--see your surgeon. Thanks, best wishes.
Thirteen weeks after surgery and sloshing
This is unusual!! Fluid collections should have resolved by now. Sloshing sounds very loud. Feeling the water shift is common with saline implants.
"Sloshing" 13 weeks after breast augmentation
Lots of "sloshing" sound 13 weeks after breast augmentation is not normal. You may have a fluid collection that is not being absorbed by your body. Please visit with your plastic surgeon so that he/she can address this for you.
Noises after Breast Augmentation?
At this point, I would say that “lots of sloshing” would be unusual; follow-up with your plastic surgeon to make sure there is no residual fluid accumulation.
What you describe is unusual. Schedule an appointment with your Plastic Surgeon for follow-up to discuss your concerns.