Pregnancy scare

So my period has been super irregular for the past few months ever since I got off of the depo shot and I recently had sex in the beginning of March and towards the end with no protection and he didn't pull out . I'm currently on no birth control since getting off the depo last year August . Last month I took five pregnancy tests and all came back negative but this month my period is one week late . I need advice . So should I just buy more pregnancy tests ? Or Wait until my period comes ?