Let down feeling

[Icryinbaseball]

My youngest is 3. I havent breastfed since she was 5 months old. My issue is I keep having a feeling of let down. It started when my niece was pregnant this past spring/summer. She had her baby in July. I am still getting this feeling. At least once a day I get that feeling. I am not around any other babies. I am not pregnant myself. Any ideas why I could be having this happen.