Hard lumpy areas following liposuction is part of the normal post operative course. When the cannula, or instrument used to removed the fat moves in and out of the body, it causes trauma to the tissue. Scar tissue forms internally, not just on the outside of the body. The scar matrix remodels over the course of one year. Being only one week out, this is not something of concern, however, there are lumps that are not appropriate and assessment from your surgeon would be the best way to rule this out.
Hope this helps,
Javad Sajan, MD