Can Flucloxacillin Be Taken During A Menstrual Period?

Hi, I am having menstruation now. But I have a boil under my armpit. My doctor asked me to have Flucloxacillion 4 times a day but I forgot to ask him whether it will affect my Menstruation.
Can you please advice me on this? I am having 5th day menstruation now. After I had 2 dose of the medicine this morning and afternoon, i feel that I am having heavy volume of period now (which normally i don't, as now is the 5th day).

Thank You very much