Help... I’m about to loose my mind

So long story short we have been trying for a while now but we’ve had no luck. My fertile window was from de 22 to the 28th. We BD a couple of days before and during. On thursday (5 days ago) I had spotting. I thought implantation bleeding because my period is supposed to star tomorrow. It was super light and brown. Almost only when i wiped. That same day I had sore boobs, nause and fatigue. Up until today the same symptoms but i went for an beta hcg in the morning and it came back at 1.20!!! So im not pregnant but im sooo confused! Please be nice in the comments below as I am Looking for support. Thanks