How is period different from implantation bleeding?

Emma โ€ข Married 22 y/o TTC baby #1 โค๏ธ April 2020 ๐Ÿ‘ผ๐Ÿผ May 2020 ๐Ÿ‘ผ๐Ÿผ TTC 12+ months Cycle 1 FemaraโŒ C2 โŒ C3 โŒ C4 โŒ Due January 2022 with our ๐ŸŒˆ

Symptoms: cramps and bleeding 3 days before period due, negative tests, blood dark brown