I keep getting boils on the same spot right before my period starts.... should i be worried?

It is something: to talk to your Doctor/Dermatologist about, even though it may be embarrassing. You may have a very mild case of hidradenitis suppurative where, for unknown reasons, the apocrine glands become plugged/obstructed and abscesses form, sometimes infected/sometimes not. Hormones related to menses may influence. It may be genetic. Various treatments somewhat effective. See Derm specialist