14 dpo and suspicious symptoms

B
I've been experimenting nausea since last night! Also my lower back hurts. Af is 1 day late. I had a bunch of other symptoms earlier but I know they were not pregnancy related since I tested 3 times until 11 dpo and only got bfn.
What do you guys think? Should I test again or these sounds like af symptoms? I've never had nausea before af but there's always a first time. 🤔 I feel confused.