Can too much caffeine cause nosebleeds, after you stopped taking so much caffeine for 3 days? I cut down on caffeine but today I had 2 nosebleeds. Or could it be because I only slept 4-5 hours of sleep? I don t feel tired how I normally would but I ve had nosebleeds. During the week when I also slept little I had another nosebleed. Should this be a serious concern?