Cold medication

Ive been trying to google this but i cant find an answer. Im not pregnant. I came down with a very bad cold ive taken robitussin and it seems to just keep me up nd not work, so i just took a tylenol cold and flu pill however i just got my mom to pick me up the buckleys complete day and night pills cause i know those work. My question is , how far apart should i wait to take the buckleys..

And another question .. Ummm they say do not take more than 8 doses a day.... Lol does that mean within the 24 hours? So if i started at 8 am.... I shouldnt exceed 8 doses til...the next day at 8 am?

My brain is so complexed....