3 Weeks Post-Op Liposuction to Thighs and Knees, Is it Normal How Tight it Feels When Walking?

I had lipsocution to my inner thighs and knees 3 weeks ago (I know it's not so long ago) and most pain and bruising has gone. But I have noticed if I excercise or sit in one place for too long that when I start to walk that the entire area feels really really tight, like something inside is about to snap. Stretching helps after, and I have tried to massage the area with the palm of my hands to get in deep - but it's a little worrying when it's hard to walk..