Fermentation smells of methane

[onemanorthree]

Fermenting an IPA using ferments yeast 04.  It's a standard IPA, comes off at about 6.6.
All equipment cleaned well throughout the process.  When I went into my fermenting room this
morning there was a heavy methane like order.  Fermentation seems fast, faster than usual actually,
and the beer tastes ok.  But the small is pretty strong and not pleasant.  The beer is also slightly fizzy.
I've seen the fizziness before on other beers and they've turned out ok, but I don't think I've had one smell like this.

Any ideas?

[nigel_c]

It'll fade. Still in fermenter it's very young.

[Will_D]

Sorry to be pedantic but Methane is odorless!

The smell of natural gas is added into the gas supply so that it is more detectable.

Do you mean it smells of natural gas?

Or is it and eggy/sulphuryi smell ( Hydrogen Sulphide)

Does it smell of the farmyard?

Acidic smells?

All the above are caused by common infections

[Enno]

Fermentation seems fast, faster than usual actually,
and the beer tastes ok.  But the small is pretty strong and not pleasant.

What temp is it fermenting at? Sounds like its fermenting a bit too hot. This can cause the yeast to ferment faster, but can also produce off flavours like ethyl acetate (nail polish, gasoline). This is especially produced during the first 48hrs of fermentation.