I would take a look at the /Volumes directory on your startup volume. It is supposed to contain only "mount points" of other volumes, with icons that look like aliases. Sometimes, though, a real folder can mistakenly get created there. If /Volumes contains a "ghost" folder with the same name as a real volume, then the system might be unable to mount the real volume without changing the name of the mount point by adding a number to it. Such ghost folders can also waste a lot of disk space.
/Volumes is a hidden folder, but it's easy to peek into it:
Finder>Go menu> Go to Folder
enter /Volumes and click Go
You should see only alias icons there. Do you also see any folders which are NOT aliases? In particular, do you see a folder icon named "Storage HD" as well as an alias icon named "Storage HD 1"?
If so, then the "Storage HD 1" alias icon represents the real volume, and the "Storage HD" folder is a "ghost". Ghost folders should normally be deleted, but in your situation it may not yet be safe to do so.
My home folder is located on this drive, and I had to remap it to reflect the new mount point name.
If you do find a "Storage HD" ghost folder, delete it, and then reboot, the Storage HD volume should correctly mount at /Volumes/Storage HD the next time, which is what you ultimately want. However your user account might not be able to find its home folder until you re-correct the path to it. I would create an additional "normal" admin user account, with its home folder on the startup drive, before trying to change anything.