16dpo no af, neg tests :(

So I am 16dpo and still no af (should have been 10/24) BUT i tested 15dpo and had a bfn :( this is cd30 and I usually have 28 day cycles with a few being less than that!! Should I test again?! I'm afraid to get my hopes up but everyday I see no af I am! It's frusterating to see bfn tho!!