Would definitely advise having her looked at by your vet as soon as you can. She could have something in her eye- they can get a little grass seed trapped under the thrid eyelid for example. Whatever the cause it sounds as though her eye is very inflamed and painful and if she keeps rubbing it could result in an ulcer on the cornea- so best to get it looked at now. Best of luck.
My 1 Yr Old Boxer Dog Has A Swollen Eye, It's All Red Inside And She Will Hardly Open It. I Noticed About Two Hours Prior To Her Swollen Eye She Kept Itching Her Face/eye. What Can I Do?
This sounds like she may have an infection that will require cream and or antibotic. Which could have been caused by her scratching the inside of the eye, OR may be pink eye which will only get worse and spread into the other eye.
I have an eight year old boxer and he suffers from ulcers on the eye that cone out if not treated, this can be very serious so get yours to the vet asap