I just dont understand

Cassie • Momma of Two Graci 5-7-15 Graeson 9-7-16! Angel Momma of Two Nov 2015 and Twin B Jan 19 2016!
Ive been ttc for 4 months took a preg test today it was neg been having light cramping all day and all my friends are getting pregnant. Someone told me itll happen when i stop trying but its soo hard i wanna make sure im healthy but im loosing hope