opened gas pipe by mistake - what action needed?

[hardworkingfamily]

I had a dripping water pipe. It was in a cramped space, so I needed to temporarily remove an adjacent pipe to adjust it. The next-door pipe looked exactly the same - however, when I loosened the isolator-valve connector, it was obvious it was a gas pipe, not a water pipe.

I quickly tightened it again.

I think I can now smell a very faint gas smell - my wife thinks I am imagining it, so it's definitely not strong. However, I would appreciate advice:
1) Was it safe to use plumbing isolator valves for gas pipes and is it okay to just reseal one once opened?
2) If I replaced the gas pipe connector, should I use a professional or is it a normal DIY activity?

I have not worked with gas pipes before.

Thanks in advance for any advice.

 

[bernardgreen]

Please get a GasSafe registered person to check the pipework.

 

[alan333]

https://www.diynot.com/diy/threads/diy-gas.8090/

 

[Hugh Jaleak]

If in any doubt, call National Grid on 0800 111999 to report an escape. Let them test the system and they'll soon tell you if there is a leak, even a slight one. If there is, and they cant repair it, then you will have to find an engineer to repair the leak and retest the system.

Gas work is not DIY, for safety reasons please engage a Gas Safe engineer.