Missed Period Negative Test Milk Dropped

I'm a nervous reck! I've tested 6 days before period the first day of missed period and both negative. I've been tired and super thirsty and trust I drink so much water I don't know the last time my urine had color to it. Then I noticed with my missed period my milk supply has DROPPED to almost none I'm barely ab

le to pump 2 oz and when my baby nurse she is dam near trying to pull my nipple off trying to get milk out in frustration. I'm starting to get depressed because I never thought I'd be struggling at 3 months with my milk supply and I either pump express or nurse or a combination every hour on the hour to keep up with my baby girl and store for dad to feed her. So my questions are have you gotten a positive later on and does pregnancy cause your supply to drop TIA ladies