It is worse in the morning, when I wake I have a dull ache in my lower back, it sometimes is worse on my left side, and I am full of wind, after passing urine, the ache is still there, and I often find it difficult to stand up straight so walk bent over for a while it does ease off, during the day, and by the evening I am fine, but it is back again in the morning. I am 53 have high blood pressure, and am on medication for that other than this I am well, I am still having periods, and am always full of wind and the back pain is worse when I am having a period. is it my kidneys?