Worried

ok Im a lil worried here, even though I dislike my job and hours I am kinda worried tht since I have been making some mistakes, or according to my boss too many. I dont know I guess I was growing into this job or at least able to put up with it. But I have been having these weird visions or thoughts like I have already been through this exact same situation before. This vision was always tht I wouldnt be here that long for one reason or the other, either if I left for another job or was fired. Well I was jsut told yesterday tht I have been making a lil too many mistakes and tht my boss lowered the number or orders tht I need to get, which has been one of the reasons for my mistakes. I go tooo fast and dont really think and look all the way, and am worried tht my time here will have to be cut short now tht I actually like this job. I dont know this makes no sense like usual but it turns out im jus a little worried now cuz I chose this job over the other one, which is most likely gone andthis job has benefits and great oppurtunities in the future for advancement, schoolin and all tht. I dont know here a little worried.