Does dairy in formula increase the frequency of ear infections and congestion?

No. Dairy (particularly cold milk or ice cream) is a mucogenic (mucus producing food), but typically this is a fairly mild effect and does not result in increased ear infections, although it may result in some temporary congestion. This mucus producing response may be more pronounced in some patients and can be mistaken for a milk allergy.
No. That would be very rare. Dairy allergies can cause skin problems (hives or eczema), or more rarely gut problems (bloody diarrhea); there's also lactose intolerance, which occurs only in children and adults (never babies), which can cause diarrhea and abdominal pain. But food allergies very rarely cause nasal symptoms, congestion, or ear infections.

Related Questions

My doctor says I have an ear infection caused by congestion. On medication&recieved a shot. My ear was unaudible since 2days ago&now my right. Help?

Bilateral. Many ear infections become bilateral. If the infection is under 7 days, it is likely viral and will not be cured by antibiotics. If the hearing is really bad or ear is painful see an otolaryngologist for possible tympanocentesis or fluid removal. Read more...
Common. For a true middle ear infection to occur you must have some fluid accumulation in the middle ear space. That fluid drops hearing perception by around 40%. The fluid buildup that led to problems in one side will often involve both over time. It takes a week or so to kill the germs and sometimes weeks for the fluid to leave & hearing to return to normal. Read more...

Dizziness, mild tinnitus, congestion, no pain in ears, sensitivity to sharp noises. Is this an ear infection?

It may be. The best course would be to go and get examined by an ENT physician. You may have some allergic reactions, sinusitis, labyrinthine dysfunction or one of another dozen entities. Go and get seen. Hope you improve soon. Read more...