Can radiotherapy for Breast Cancer cause chest pain?

I’m a third of a way through radiotherapy for breast cancer. I was eating a meal yesterday and was really uncomfortable swallowing it, first time it’s happened, today though it’s really uncomfortable, I’m wondering if this is due to the radiotherapy. I’m not having treatment on my collar bone but obviously I am on my breast bone, I’ve googledit and got conflicting info, has anyone else ever had this, even drinking water is uncomfortable.

Thank you x