I tried a co-worker's jalapeño IPA yesterday. All he did was take his favorite IPA and add a raw jalapeño (cut in half lengthwise and seeded) for the entire 60 minute boil. Then took a second pepper, roasted it and added it to the secondary with the dry hops. He said a little bit of char on...
You may not have gotten your priming sugar mixed up well enough. I usually add mine to the bottling bucket before transferring from the fermenter. If you add it after the transfer, you may not get enough of a mix. Insufficient mix would result in some bottles being over carbonated and others...