I am so scared to test 😕 don't know what to do....

So according to glow as I imputed more previous dates of my period it changed my af date from 06/15 to 06/12!! I mentioned before I have no tender breast pain like I normally do before af arrives and this morning I woke up and no af so it changed the day on me again.. I want to start testing but I can't seem to get the courage to do so. I am so scared it might be negative.. This by far is the longest cycle I have ever had.. As of today I am 11 dpo. I DO NOT KNOW WHAT TO DO😔 when should I start testing?