@RobbDc, can you explain to us (if you remember) how you got to Electrum wallet in the first place? If you went the normal way, then you downloaded Electrum and created a wallet inside it, and then you got a seed of 12 words that you had to save. If by some chance you didn't do that, and you didn't even save the wallet files, then you actually have no way to get possession of your Bitcoins.

Try to remember if you saved your seed or private key - because even though there is a possibility that you didn't know what you were doing, that watch-only wallet must have been created on the basis of something. There is also the possibility that someone actually sold you only a Bitcoin address and convinced you that you have Bitcoin in something we call a watch-only wallet.