Hopefully you also have a glass in tank thermometer?
Test strips are very inaccurate but they're better than nothing. If you have nitrites your tank is not cycled and you should read this guide about the fish in cycling: http://www.bettafish.com/showthread.php?t=47838
You will also need an ammonia test kit. You will need to increase water changes to deal with these levels. The guide talks about how and how often to test and do water changes while your tank is cycling. Once it is cycled, you will need weekly water changes of at least 20% weekly. Also the tank will need to be at least 5g to maintain a cycle. Never filter anything less than 2.5g and the 2.5g will require extra work/ more and larger water changes.
If you can't find Kanaplex (I would get a phone book or use yellowpages.com and call around) then get something else.. Maracyn Plus (not to be confused with Maracyn or Maracyn II or Furan 2)