I Had A Hysterectomy 4 Weeks Ago. The Last Few

I had a hysterectomy 4 weeks ago. The last few days I have had painful lumps appear in my underarms about the time I would normally have my period. I have experienced this before & was told it was hormonal. I had mastitis after my 2nd pregnancy. I have routine mammograms & all have been normal. Just had my most recent right before my surgery. I have experienced this before & it was hormonal, but should I be particularly concerned with it after my hysterectomy.