Asking other moms; Who had Sore breasts and milk supply drop around 10months pp?

Ftm here 26f and 9 months pp. sooo my baby has been on the boob more lately, waking up every 2 hours at night to feed and today I noticed when I went to self express it’s so hard to get anything. A few drops but that’s all. Usually I have no struggle so this is odd for me! I also noticed my boobs are a bit more tender, but I just figured that’s from her whaling on me and just being rough.

Period returning? I know that’s usually a symptom but I’m still breastfeeding often, or self expressing to put in my daughter’s food. What were your symptoms of period returning? When did it return postpartum? Any other reasons my supply might be low?

Edit; I have talked to a lactation consultant and I have an appointment next week