Backstroke and 500 free help

I guess I'll make this sort of an introduction thread as well. I'll make that part quick so we can move on to business. I started swimming a year ago. By "swimming" I mean training for competitive swimming. I had already known how to swim all the strokes. I was a freshman going into sophomore year in high school at the time. What you need to know is that I taught myself all the turns, racing techniques, and starts by watching YouTube videos (NOT expert village) and practice. To prepare for my swim team in the winter, I swam 500s and 1000s to build up my endurance. I wasn't really sure what to expect, and I had know idea what stroke I would be good at. When time came, I found myself in the distance world, swimming 500 freestyle races. I swam 6:40ish 500s. For a noob swimmer, I've found that isn't half bad, and I got like 3rd or 2nd place in my races. Bu the other 3 events I had to do I usually sucked at. My coach put me on breaststroke races, and I didn't know how to sprint. (as in, I didn't figure out until half way through the season that you need to hold your breath in sprints) So aside from the 500, I did crappy. I think the only reason I didn't fail as much at the 500 was that I had spent all summer and fall swimming 500s and 1000s in preparation. In the spring I didn't have time to do anything, since I was too caught up in school work. But as soon as summer came again, I hit the pool just like the previous summer. This time, with a better idea of the swimming world. As soon as I started training, I found I could swim a 29 second 50 back stroke. Now, to some of you people here that are very advanced, you probably think that sucks, but I think it's good considering I've never had any formal back stroke training. So, I've decided to build off of that. That, and 500 free style. I'm going to make those my main events, and go from there. So my main question is, what sort of workouts should I be doing to improve at this point? I've been able to hold a 37 second 50 back stroke for 10 intervals so far on the minute. But my 100s are really suffering. I'm swimming 1:20 intervals on the 100 only 5 times in a row before I have to stop. My main problem with back stroke is also the start. My dolphin kick is weak, and I could stand to improve it. Finally, my 500 is still where it was before. I'm trying to push it down sub 6:30 before the season. I'm not really sure where to start with the 500. There's nothing particularly wrong with it. I just need to increase my endurance I guess. As I was saying, based on this whole.....essay (lol) that I've written, what sort of advice do you any of you have to give? I'm doing whatever I can at this point to improve. I don't know what it is, but I've fallen in love with swimming and just want to keep getting better. Keep in mind, I'm still a beginner, and still have a lot to learn. I really appreciate any help I get from you veteran swimmers. Thanks a thousand. :angel: