Does my back pain sound like a strain?

Hi doctor,

I am getting recurrent back pain and I believe that the pain is in my rhomboid muscle. Usually, this happens after sitting for a while or while changing the position. Most of the time it occurs from a normal movement. I feel that after some movement the pain starts almost instantly. I cannot tell if I am straining it every time or if it is just knots and trigger points. So, I do not know whether to apply heat or ice. I am just taking Ibuprofen.A few years ago, I pulled that muscle pretty badly. It took a few weeks to heal. Since then, I have had these flare-ups. It is never as bad as that pull and they have lasted now for two to five days. This morning, while getting out of bed, I felt a spasm or a knot or strain. I tried to ice it, but I think it made it worse. Is hot fomentation safe? Does it sound like a strain or pull or a recurring knot?