My ds is nearly six months, I'm bf, my periods are fortnightly!

[Chocolateporridge]

Is this normal? I've marked my periods on my calendar and each one is two weeks after the start of the last one, they last four or five days.

I'm still breastfeeding but during this time my supply has substantially dropped and I've had to start topping up with formula.

Should I see the doctor? This didn't happen with my dd!