DEPO?!πŸ€·πŸ»β€β™€οΈπŸ€·πŸ»β€β™€οΈπŸ€¦πŸ»β€β™€οΈπŸ€¦πŸ»β€β™€οΈ

Does the depo ACTUALLY last 12 weeks??? Like when should I start getting more cautious and worried about pregnancy