Unexplained bruise over left kidney-30 weeks pregnant

Do any of you ladies have any input on what could be the cause of this?? I woke up this morning with back pain in this area,just enough that it’s uncomfortable to moderate pain, but I figured I slept wrong last night. Tonight I had my husband help put icy hot on the area and he asked if I had ran into something. I said no and he took this photo. Should I be concerned??