. It is possible that you are dehydrated and that this is causing your headaches. Make sure to drink plenty of water, at least 2 liters a day. You can also take a combination of acetaminophen and ibuprofen for pain relief. Check with your pharmacist to make sure you are not exceeding the maximum doses and to see which painkillers can be combined with your cold and sinus tablets. Your symptoms may last up to 7 to 10 days, and the fever should decrease and disappear within the next 72 hours. If your symptoms worsen, contact us or info-santé to see if you need to see a doctor.