hi, it may be problems of your add-ons, you should be fresh browser without more plugins or some additional tools like rank checker. try to do all your seo work on manual basis bcz this is the best way. Thanks
it can be happen but you need to worry about it because competition for this phrase is more so other website also working for seo activity... can you let me know one thing have you seen other website along side is it happen with them also or not if not then i will give some tips how to stable your results..