Anyone know what this is?

Hiya, for a few weeks now I have had a weird sensation on my scalp, just above my temple on the right hand side is really sensitive. It feels sore just to brush my hair or lay on it, it feels like a headache when you touch it but there is no pain otherwise like when you press a bruise (but it isn't a bruise and doesn't hurt the same way a bruise does). sometimes it is worse than others and sometimes it isn't there at all. I am thinking it may be something to do with a blood vessel close to the surface of my skin what with the extra blood flow etc during pregnancy but I have no idea.
Has anyone ever had this or know what it is? It's really odd (and annoying)!!!
xxx Hannah xxx