I know Iron is important but was wondering if donating blood one week out from a marathon is a no no.

I am someone that is recommended by my doctor to donate blood. I guess my body does not naturally dispose of iron fast enough and therefor it is recommended I donate every 6-8 weeks.

I was wondering if doing my last one just one week out from the Marathon could have lead to my fatigue I felt during my Marathon in Chicago this past weekend.

Thanks,