answer:

There is a definite link to a baby not nursing as much and then getting you period back. As soon as you supplement with anything, even a pacifier, its a missed opportunity at nursing and your body starts to think it needs to start getting ready to conceive the next one.

at 7 months old it could also be related to night nursing. If he has recently stopped nursing as much at night, the body also has the same shift. I don't think that your milk has depleted suddenly. there has to be a reason why it would if he were interested in other food etc.

He may seem that he is less interested but he also might just have gotten so much more efficient at nursing. Often , women also think that because they don't have the same full breasts they did when they started that means a decrease in milk but that not true either. its more along the lines of your body has learned how to accommodate the milk supply your little one needs. Just continue to nurse on demand. and the baby will befine. if he is where he needs to be developmentally right now, ( which also could be why he has no interest in food.. when babies get to a physical developmental milestone they often give up on food being their main focus ) then you have no need to fear. I wouldn't stress trying to get him to eat. He will eat when hes hungry. If we force them, its where food issues start in and lead to obesity and other food related issues...

Common worry for many moms. But I am sure he is well. So please try not to worry unless there are developmental delays or hes failure to thrive etc... which you wouldn't have gotten this far if there was :)