Ultrasound No sac found

Bfp on the 5th. This is my cycle attached....I’m irregular anywhere from 29-35 cycles. Another bfp on the 6th CBD 1-2 weeks on the 8th. Had bad back ache and cramping also felt like evening nausea disappeared the last few days, don’t really feel pregnant anymore. Went to ER today, urine test positive for pregnancy, didn’t get hcg blood back yet, ultrasound found free fluid on the right and a bit on the left and no gestational sac was found.

Can anyone share their ideas? I go back in tomorrow for more blood, possibly another ultrasound. Sounds like they’re concerned about ectopic pregnancy. Not even sure how far along I am as I BD more than once, 17th, 22nd and 29th.