Day 6 after Vaser Lipo and started to leak, could I have an infection?

I am day 6 post op after vaser Lipo. The garment is giving me terrible back ache and hurting my spine so last night I decided to try and sleep more flat on my back. After drains were removed I’ve been changing my dressings and they have been perfectly clean every day. After last night I have woke up with morning and a incision on the top of my bum is leaking. Do you think this is down to the way I’ve slept or an infection? I’ve been taking antibiotics every day since surgery.