You definitely should go see your primary care doctor
about this issue. Nose injuries are very common and they are rarely serious, but it is important to have a thorough examination to rule out anything that might need additional medical treatment.
First of all, your doctor will be able to determine whether or not you have broken a bone in your nose. Although simple nose fractures may not require treatment, more complex nose fractures do need to be followed closely to make sure that they do not lead to significant deformities down the road. Furthermore, it is important to make sure that you do not have a large bruise
inside the nostrils, as this can lead to trouble breathing and significant pain if not drained.
Furthermore, your doctor will be able to perform a quick examination of the other bones in your face; sometimes when you bang your head like you did, you can damage other bones other than those in your nose, and your doctor can rule this out. It is also important to take a look at the teeth to make sure they have not been damaged in the incident.
Get in to see your doctor as soon as you can!