There distinction between
"authorised shares" the maximum amount of shares the company is able to issue; and
"issued shares" the number actually issed to the shareholders
A company can have an autorised share capital of 1 million �1 shares, but have only issued one or two of them. Subject to dealing with the matter properly it could issue more shares if necessary.
The price for which the shares are issued is a matter for negotiation between the company and the shareholder.
The shares may have a nominal value of �1.00 each but be issued at �10..00 each. This requires proper reflection in the accounts as the share capital is only �1.00 per issued share, but there needs to be a "Share premium account" showing the other �9.00.
The actual value of the shares will depend on the trading performance of the company from time to time, and how much a third party would buty the company for.
When you isse shares in a company it is necessary to make a return to Companies House to reflect what you hvae done. I am unsure what it is that Companies House have returned to you, but it is all to easy to send them the wrong form!