Pictures have a brownish tint

I'm a beginner, still learning how to use my new Lumix DMC-G7. Both on my computer monitor and big tv screen, many of my pictures seem to have a sepia tint. I can't figure it out. Today, I even told my friend when we were down by the river, "remember what the color looks like" and he agreed that on screen it looks browner.
Also, a lot of photos seem over exposed. I'm mainly using Aperture Priority or iA mode. Pictures have a brownish tint