Very sadly....my period has returned. DS is 6 months and we recently (within the last week) started having him sleep in his crib at night because no one was sleeping well at night. This new arrangement isn't loads better, but at least we are all getting more solid stretches. Anyway, I'm so bummed that the switch probably brought on the menstruation. Will this effect breastfeeding now that I will most likely have a regular menstruation? Can I continue to breastfeed exclusively? Help.
Yes! You absolutely can continue breastfeeding exclusively!
Many babies do start solids around 6 months, but if you weren't planning to do that yet, that's still ok.
If you have a decrease in supply during the first few days of your period, that's ok and normal. I never have experienced that myself, but my baby was more like 10 months when my periods returned. But continuing to nurse frequently and staying hydrated and well nourished should minimize any supply dip.
I think you'll be fine!