Does Sleeping on Side with Seroma Cause Extra Fluid?

i had a tt in Feb 9 2012. my left side is healing nicely. my left side had a seroma and caused my incision to open up. the ps stitched me back up and did aspiration and removed . i tend to sleep on my left side. does that cause it happen and heal slower? because my nurse says Dont sleep on my left side. My right drained was taken out at one week and left side at 3 weeks