My braces are making my teeth worse?! :(?

I have had braces for about 20 months (which was how long I was supposed to have them) and I'm just really aggravated right now. Before I got braces, my teeth stuck out a bit at the top and there were two teeth that were tucked under my two front teeth, which were aligned right next to each other and were straight. My last appointment was three days ago, and they bent my wire (whatever that means) and now I'm noticing that my one front tooth is starting to get tucked under the other!! WHAT THE HECK IS GOING ON?! He said I'm almost getting them off and they're just getting worse! The same thing happened to my bottom teeth. They were all straight except for two teeth that overlapped and my two front teeth on the bottom were straight and now they're crooked and have been like that for a year now! Are they ever going to get better? Because I am so mad about this, my teeth better be perfect when they're done! You have to look close to see some of the crooked teeth, and I'm afraid he might not notice it and just take my braces off. As much as I hate braces, I'll keep them on for another year or so until they're perfect! Can someone that used to have braces tell me if this happened to them? Should I be concerned?