Implantation at 4dpo?

I know implantation happens from 6-12 days after OV this is mine and my husbands first cycle TTC and didn’t know if it could already be happening? I woke up this morning with mild lower back pain, and I never really cramp during OV so I don’t think I’m late on that. And I have thick white cm, I know it’s highly unlikely and I’m probably just reaching for straws, I really want this to work! Thank you! And side note, if anyone has any advice on what a good excuse for not drinking would be😂 even to fool the hubs, we are going to a concert this weekend and even if I’m not pregnant, I don’t want to risk anything.