I broke my back in 2016 and have multiple slipped disc due to the fractures but when I have what I consider an “actual period” the knots in my back increase and get much larger. I my self can not go to a chiropractor because of my past injury but I have talked with some other girls with this exact problem that swear by their chiropractor they keep an apt monthly around their cycle. I do heat and I have a back heater/messaging thing that rubs my knots amazingly. I also love to put bio freeze on my lower back then use a heating pad. I feel for you hun hope maybe these few things also help because I have heard chiropractors can get expensive especially with insurance restrictions.