Light AF & BFN , confused! Can anyone help

[Joyful2]

Hi MN
My cycles are normally 30-33 days.
DTD around ovulation (according to Flo app).
I began to spot when AF was due. 2 days of v light spotting then one day red when wiping and today it’s gone back to light spotting nearly nothing.. So 4 days of barely anything that’s not needed a pad.
According to Flo app I’m be around 18DPO and my tests are coming back BFN.
Thought I could see a faint line but I was clutching.

With my first pregnancy I tested like MAD and got a BFP at 8DPO. I’m kidding myself I could be pregnant this time with BFN at 18DPO right?
Has anyone been through this?

Also wanted to add I’ve no AF symptoms. No sore boobs, just a very bunged up nose since the spotting without a cold.

How sure you that was defo ovulation? Just thinking if it was later than you expected and it’s implantation? You will know in a few days for sure if this is the case as you will get a positive test. If not maybe get some ovulation tests and check it matches the flo app

@Georgethecat1 Actually that’s a good idea, to do the ovulation strips alongside Flo app.

Funnily with my first according to date baby was born, I conceived few days after AF! So I’m aware you can ovulate at random times in the cycle. I think if I am out this cycle my next plan is the ovulation strips to be sure.