Why do you feel heartburn after taking three clindamycin pills?

i got heartburn after taking my 2nd pill, i think, because it was right before bed.... you are not supposed to lie down 30 minutes after taking it and you should make sure you are taking a lot of water with it to dilute the medicine so it doesn't burn up your stomach and throat..... i have an emergency visit with my regular dr today to review.... i have just taken my third pill because the amox wasn't strong enough for my tooth infection and i ended up in the er. good luck.