Plugged duct?

My DD is 10 months old and although she has tried solids, she still prefers to nurse a lot. She's up a few times each night to nurse some more. Since she was 2-3 months I've been experiencing recurring plugged ducts in my right breast. Most of the time on the underside of my breast in the same place. I also have a milk blister that seems to come and go. About 6 months ago I had mastitis in the same breast. 2 days ago I experienced my most recent plug in the right breast. It took about a day to get it out. I use a heated rice sock, hot shower, and massage while nursing in various positions. Anything to avoid these plugs turning into mastitis again! Yesterday, I thought I was plug-free but I started experiencing pain on the underside of my right breast again but this time without the hard spot I always get with my usual plugged ducts. The pain has continued today. Worse after DD hasn't nursed in a couple of hours. I still can't feel a hard area at all. It feels like a bruise, without the mark. It's very painful to the touch. I don't know what to do. Does this have anything to do with the plugged duct I had 2 days ago? Is it something else? I'm worried