late period, negative tests

So I am currently 11 days late for my period however the past few days i have been feeling crampy on and off in my lower stomach where i normally get cramps and in my lower back how i usually do when i start my period. I took two tests so far and both came up negative right away but then last night I spotted a little and figured i was going to start so i put a tampon in. When i went to change it there was nothing on it so basically it was just me spotting and now i’m freaking out. I got off of birth control after 4 years this time last year and ever since my period has been a irregular. Some months it was late by like 6-7 days. Some months it was earlier by 5 days and now here i am sitting at 11 days. I am STRESSED. I like to over think things so i’m freaking out wondering if something is wrong with me. Has this ever happened to anyone before? can someone please reassure me this is ok? or just give me some guidance? i was going to go to my gyno but they are closed until tomorrow so I’m looking for answers until i can go.