Pea size lump armpit breastfeeding

I’ve been breastfeeding 12 months and found a pea size lump in my armpit which is provably a swollen lymph node. Has anyone else had this? I’m not talking about when milk first comes in and you get lumps and clogged ducts. I’m wondering if anyone has had this after breastfeeding for at least 3 months or more. If so how long did it take to go away and what did you do? I plan to get checked. I’m just trying to get others experience with this. Please don’t comment if you have never had this. Thank you