Well, I'm relatively new to running myself (thanks to some tips and encouragement from Riley back in the fall---Thanks Riley!) and am loving it. I ran 3.5 miles today for the first time.
The other ladies so far have really stressed the shoes, and they are correct. Also, everything I have read (and I have been online and flipping through and reading in bookstores as well) stresses over and again, not to do too much too soon. Your bones need to adjust to the impact. It really is a weight bearing exercise. Also, the small little muscles/ligaments in your joints need to get stronger too. And that takes time. I, too, have read (and followed) the 10% rule as a guideline. It isn't to increase by 10%, but to increase by NO MORE THAN 10% per week. That means, LESS than 10% per week. And if you are "feeling it", then go with much less, if any.
I made an early mistake of trying to run on a blacktop highway, only the first 1/2 mile was on a curve. Not smart. Biomechanics do not work properly when running on a sideways slant, like a curve in the road. Taught be very quickly to be aware of the biomechanics of running. Not just the surface, but the slant, slope, material, and running form itself. No leaning forward (which, having run/walked on treadmills for years in gyms...it is just what happens when I use a treadmill---and I'd bet dollars to donuts that you do too). You should be upright. Shoulders relaxed. Head even (book on your head).
And slow down. I was trying to push too hard with speed, and ended up not being able to finish a distance I had already "conquered" (a whopping 1.4 miles.. whooppeeee ). But I could suddenly not finish even that. Why? Because I was trying to run too fast. Not on purpose. I just didn't concentrate on running slowly. Once I did, bada bing bada bang: 2.25 miles on my next time out. Once you start seeing the distance increasing easily, is it SOOOO easy to push it. Don't.
When I hit 2.4 miles, I made a conscious effort to slow down and measure each and every run, so that I did not go to far. If I wanted to keep moving at the "end" then I walked until I felt done.
I would try to visit a specialized running shoe store. Is that where you got your great shoes from? I didn't. I think I just got lucky going to a Dick's Sporting Goods, and "happening" to pick up a pair that is right for me by luck. I haven't had any issues with foot/ankle pain, and the only knee pain I had was directly related to trying to run on a curved slope. Took me almost 3 weeks to heal from that one run. :(
Also, I didn't pull your profile, but how long post-partum are you? Your ligaments may still be a little loose from the pregnancy/hormones, and you might just need to slow down some for a while longer.
Good luck, and happy running.