It sounds like you might have tinnitus which is a symptom that is related to hearing loss. Tinnitus is when you're able to hear noise or sound that is not coming from an outside source within your head or ears. It can also be consistent or occasional. It's good that you've made an appointment with a professional but if you'd like to do some more of your own research, this is a good website to start you off http://www.nhc.com.au/how-hearing-works#6