Beta levels and progression

Ang

I got my first positive at 3 days before my missed period (test one) I got cramps and pink discharge with test two and three. My beta levels were tested the day before my missed period and they were 24 (test 3). Now I am one day after missed period on the 5th test. Does 24 seem to low for 14 DPO? Also why did I spot after a positive :( I’m super concerned