What Causes Heaviness In Head Post Epley Maneuver?

hi,I am 37 yr old woman. i was diagnosed BVVP vertigo 3 months back. i was doing Brandt off exercise regularly. 1 week back i had severe balance problem post which i got Epley maneuver done by GP,my problem is - i have heaviness in head post epley maneuver. is it common post effect after the treatment. how many days will this persist. kindly advice.Regards Veni