Hello. I have been dealing with swollen lymph nodes for about three to four years now. Rarely are they ever tender to the touch. However, I have been noticing that under my ear and behind my head right under my skull there are hard lumps. They are not visible only if you touch them. Im scared they are cancer tumors since cancer tumors are extremely hard are irregularly shaped. Any advice as to what it could be. Recently had blood work done that came back within normal range but I know that does not necessarily mean anything. Thank you.