I have really intense headaches, my secretions are yellowish and green, I sometimes have chills but I don't have a fever.

Based on the symptoms you described (intense headaches and greenish secretions), it may be a sign of a bacterial infection. You can try taking a decongestant if appropriate for you, but if your symptoms do not improve in a few days or if you develop a fever, it is recommended to see your family doctor. You can easily book an appointment with a doctor through various websites or consider a telemedicine option for a fee. It is important not to use expired sinus rinse solutions. Hope this information helps.