I might see the possibility of a nice loop then. In the morning (I assume home is up north and work is down south), take the 5.3 mile southern-overpass route, and on the way home, take the 10.9 northern-overpass route. I bet the southern overpass is still pretty nasty even when you're going westbound, but it looks like it would be a lot better than the eastbound direction (which I agree, looks really bad). At the least, if you're anything like me, I bet you could soon convince yourself after a few weeks of riding 22 miles round-trip that it's a worthwhile tradeoff to take on increased risk of death for the opportunity to ride 5 fewer miles. :-)
If you managed to do that, you'd be doing a clockwise loop, giving you mostly fast and simple right-turns for your whole commute, you'd be able to take it easier in the morning since you wouldn't have as far to go, and then in the evening you'd have that sidewalk/bike path on your side of the road. And you get more variety in your commute!
A 10.9-mile one-way commute is definitely up in the higher-end of the bike-commuter distribution curve, so be proud of yourself for making it in at any speed. You'll certainly get faster with more practice. But don't push too hard to start, just make sure you make it home alive tonight and then there's no shame in taking a day/weekend off. Better to slowly build up than burn out and give up.
As for your hands, a few things. First, yeah, you'll toughen up over time. Do you have cycling gloves? If not, they can reduce some pressure and make things more comfortable. Then, were you riding with your hands "in the drops" (down on the lower part of the handlebar) for most of the way? That might just be too low of a position for you, which puts more of your body weight on your hands. I ride with my hands up on the brake hoods most of the time, only going down in the drops when I'm fighting a headwind or really want to make good time. But also just switching between the two (or more) positions can mix things up and help avoid discomfort in any one position.