The symptom of eyes floaters will represent the black dots which float follows the movements of your eyes, just like flying mosquito. The shape of the dots may be circle, oval, spot. The vision will be affected by this symptom in certain extends. It may be caused by eye inflammation or intraocular hemorrhage. It may affect the retina and become worse. The allergies may cause the floaters but I suggest that you go to doctor to check the detailed situation for sure.
Yes, it can. When you are allergic these days, the dust around you may not avoided by just blinking. Or you have to sit in front of computer for a long time. The above two things may get your eyes red. If the bloodshot of eyes can't be released totally, there will be floaters in your eyes.