I Am Having Issues With My Vision Tunneling And Then

I am having issues with my vision tunneling and then going black. It seems to happen when I first stand up and start walking. It will be fine at first and then it starts to tunnel and then goes black. I have to stop and hold on to something because I feel like I might fall and my balance has been off and my vision seems hazy in a way. I do have what is called Relapsing Polychondritis and was just diagnosed about 2 and a half months ago but this is new.