We continously have unprotected sex with my boyfriend and i take morning after pill after, i told him i'm tired of the pill and he suggested i take contraceptive injection, can you please advise on this?

See a local doc: Birth control injection/ pills are considered serious medication and must be chosen based on many factors. A proper past history, family history and reproductive history are done first. An exam is necessary. Personal input on a variety of types would also be considered. There is no "best one", there are the ones that work out based on selection by a trained doc and proper follow up.