Wound not healing

Hi all
Part of my axillary scar has opened up under the skin, I think because of pressure from a seroma. I have a dark purple round bulging area about 1.5cm diameter and I can feel the wound edges are apart. I have been taking antibiotics for two weeks. I wondered if anyone here has experienced anything similar and if they have, how long did it take to heal.
Many thanks

I didn’t have it with my axillary scar but the wound where they opened me up again after my mastectomy took over 7 weeks to heal . I had to pack the wound with medihoney every day as well as have the wound cleaned a couple of times by the surgeon. Ask the breast care nurse to arrange for someone to have a look at it.