Should I get checked out ? Breast problem

Sorry TMI. I’m just a little nervous . I’m 5 weeks post partum and breastfeeding. These past few days my left breast has begun hurting more and more . In the hospital baby had trouble at first feeding on left side but does fine now and I feed him alternating sides , pumping in between . Latch is good too.

My breast itself doesn’t hurt , just the nipple/aerola area . Where the big veins are . Today I was feeling my breast and I found a pretty big lump . Where as my right side is completely fine no lumps at all . My grandma had breast cancer and is in remission now so I’m a little worried . Do u see any signs on my actual breast that could indicate it . I can’t tell on myself

Forgot to mention my left arm has been numb all week as well , not sure if it correlates