Calling the experts.thanks

So I'm 14 dpo today but when I entered my temp yesterday it went down cover line and changed my dpo so now I'm 13 dpo.well I've tested negative and I'm only spotting Brown.when I temp today it went slightly up above cover line 97.49. I know I'm probably out and should wait for AF but since this is my first month charting what does this mean? What should I be looking at I'm still trying to understand my chart.is it normal to go back up after it has dropped?also is it normal to change your dpo?