Hello, I Am Experiencing A Positional Vertigo. When I Go

Hello, I am experiencing a positional vertigo. When I go to sleep when I turn on my right side, everything is spinning around me. During the day, I am OK, no dizzy feeling. Since I am sleeping in an armchair sitting in the last 2 days, I would like to have a little rest over the weekend. I never had such an episode before. I am 63 year-old woman. Can you advise me some medication over the counter I can take to have a good night sleep?