So confused

I’ve been TTC since May. My cycle has been 30 or 32 days every month (alternates between the two every month) this month I took OPK as usually, I got my LH surge on day’s 20 & 21 when I usually get it on days 16-17. Now I’m on cycle day 35 and no BFP or AF. I follow a few apps and am late 2-3 days on all and keep getting pushed back... I’ve taken two test and we’re BFN... I’m confused why my cycle is weird this month after being so consistent for 5 months