What you specifically need depends on your unique requirements, much of which can be ascertained from adequate pathology testing.

Please speak to your GP regarding the following:

A mid-luteal (7 days post-ovulation) progesterone and oestrogen (estradiol) blood test. Alternatively, please order here.
If you are also experiencing heavy menstrual bleeding (HMB), please also request:

A pelvic ultrasound, to be conducted in the days post menstruation.