Sinus Infection?

Well, I'm not sure if it's a sinus infection, I just don't know what to call it. The sinus under my eye hurts when I blink (and just hurts in general. but like the top of it hurts most.), and feels really congested, yet the side of my nose, that it's on, well, I can breathe really well. My mom said that my eye was bloodshot (like under my lower eyelid) And when I stand up it feels like my head it pulsing.