Tenderness At Back Of Head, Small Painful Lump Behind Left Ear, Chronic Lower Back Pain, Oxycontin, Oxynorm

Hi, I have extreme tenderness at th back of the head where the neck starts. I think this is called the occipital bone? I also have a small painful lump behind my left ear and when pressure is applied it hurts quite bad. Im 35 years old woma, 173cms and 94-95kgs. I was 80ish kgs till a year ago untill i started suffering chronic lower back pain around the area of my sacrum , coccyx and hip area and became very depressed and was quite sore when i woke in the morning. The back pain restricted my excercise and i gained 25-30kgs. I have in the last 4months lost 10kgs but the pain has not improved which my doctor said it would. If anything recently it has worsened. Im wondering if my back & sore head are related. The sore head and lump concern me but my back & hip pain are the worse problem. It has affected my family life quite badly and im getting quite depressed and even thoughts of suicide enter my head. I take 20mgs oxycontin twice a day & 5mgs oxynorm 3 times a day, this used to help slightly but recently it has stopped easing the pain. I also have two lumps on my lower back(episacral lipomas i think they may be called) which are very painful. My back pain is worse from sitting for long periods, driving and being on my feet for long periods. Lying down and resting only eases the pain slightly. The pain often radiates down my buttocks and into my legs. Please do you have any idea on either of my problems? Im at my wits endThankyou