The space you purchased is in iCloud. It is not on your phone, and there is no way you can use it directly on your phone. The phone comes with whatever memory you purchased it with (8, 16, 32 or 64 GB) and that number will never change. You can use iCloud memory for backups, for syncing your mail, contacts, calendars, notes and photos. You can also use it for storing non-iTunes music to stream back to the phone (iTunes music also, but the storage for that is free, and is not part of the storage you purchased) and Documents and Data for apps that are iCloud enabled (such as Apple's Pages, Numbers and Keynote apps).
Apple gives you 90 days of free telephone support when you buy an iPhone or iPad. I guess they figure that 3 months is enough time to get your startup questions answered. You also had the option of buying AppleCare, which would have extended the 90 days free telephone support to 2 years.
You can still get free support from Apple by going to any Apple store, and from other users in this user-to-user support forum. And frequently user support is more useful than Apple's, because users don't have Apple's lawyers overseeing everything that is said by Apple employees.