If have bought a stock but it has now closed, is that a bad thing? Did I lose the buy or can I wait until the stock opens again ?
Do you mean you placed an order and it wasnt filled?
UK 
standard market open times are between 08:30 and 16:30 Monday to Friday.
USA 
standard market open times are between 14:30 and 21:00 Monday to Friday.
You can click on the “market open/close” icons to see:
So you can trade EQs within these hours should you wish to, and retain ownership outside of these hours if you’re long.
I placed the order and it went through, a few hours later it said market closed meaning that it will open tomorrow. So my question is will the order still be there tomorrow when the market opens again ?
Once the order goes through, you own whatever you bought. It will always be there until you decide to sell it.