I have had a root canal treatment which finished about a week ago. now, i have pain in my temple and back of head and feel generally unwell. what should i do ?

May be related: You might have an infection, but it needs to be examined. Call your dentist so that it can be determined if you need an antibiotic.

Medical issue?: Your symptoms do not sound typical of issues related to root canal therapy. It sounds more like a medical issue. Perhaps you are coming down with something and should see a physician.

MFPDS: If the occlusion was altered, it could be a mfpdsyndrome or as mentioned before could be some residual infection and much more likely just not related to your teeth or root canal at all.