Lump behind ear

Hi,

I am unsure what to do. I have been feeling a lump behind my ear for about a month. I can feel it is slightly bigger. I went to the GP and he said he could not feel anything. I don't understand as I can feel it really well. I came out of the doctors feeling silly and tearful. 

I do not have any other symptoms but this lump is concerning me but now I feel foolish asking to see someone else when the GP said he can not feel what I am feeling.

I am unsure what to do now.

Am I being silly?