I'm 3 weeks pp, and at my 2 weeks check up my dr cleared me for light exercise. She said mainly walking at this point. There's no rush, your body is still healing from a big event, and trying to push it will just make it take longer to get back to before. Maybe try taking baby out in a stroller for a walk when its warm enough. :)
I would wait until you check with your doctor at your 6 week check up. Better be safe than sorry..and since your down to your pre pregnancy weight just try to maintain it for now by eating healthy.
What's the rush? Doctors suggest waiting 4-6 weeks for a reason. You might feel fine but your body just went through major changes over the past 9 months. You should give it a chance to rest and heal completely.