I take a pregnancy test and it show negative but am spotting for 7day now what is going sometime you see it and sometimes you dont what is going on w?

Your period? You may be having your period or a variant of a period which can be encountered in young women. However, if spotting continues you may want to check with your gynecologist.
Not pregnant. If you have a negative pregnancy test and vaginal bleeding then you can be pretty sure you are not pregnant. If the bleeding continues for more than a couple more days see your GYN.