My oboe plays lower octaves then it is should play.

How low are the notes coming out as compared to a piano?

weird my oboe does that too and my band teacher says to just make your lips are corrected and that you have the right embouchure but idk cause i am only in 5th grade and i already play the oboe!

Sounds like you've got some water in your octave keys. Use some pad paper and get it out.

Sometimes the octave vents get blocked with more than water which will cause this. The only way there is to clean out the vents = really best left to a competent technician or oboe player/teacher.