Spotting, which can happen with a bunch of different methods, does not make you lose that much blood, even though it might seem like it.[1]
Still not working? You may have more luck with a method that provides estrogen during part of your cycle. Consider the pill, patch, or the ring.
Try a different method: Hormonal IUD and Non-hormonal IUD
References:
- Rowlands, S., & Searle, S. (2014). Contraceptive implants: current perspectives. Open Access Journal of Contraception. Retrieved from https://www.dovepress.com/contraceptive-implants-current-perspectives-peer-reviewed-article-OAJC