¿Fuera o iba.......?
 

and if i didn't go today they would've raised the fine
y si no fuera/iba hoy habrían aumentado la multa

its a hypothetical situation so should it be fuera?

It should be fuera, yes.

I would say "y si no hubiera ido hoy habrían aumentado la multa" = "And if I hadn't gone (although in reality I did go), they would have raised the fine."

"Y si no fuera hoy..." = If I were not to go (I haven't gone yet, but I still have the opportunity to go).

Y si no hubiera ido hoy habrían aumentado la multa.
Si no iba hoy, aumentaban la multa. (colloquial)

"Y si no iba hoy habrían aumentado la multa" is not standard grammar but I think it's OK with Pragmatics as natives can easily parse it. It stands between a colloquialism and a little bit of an anacoluthon. A reason for it is avoiding the perception of a still pending increase that may emerge from using past imperfect exclusively, so the perfective touch added by condicional compuesto says it is all over and the fine's increment has been averted for good.

Somehow the sentence in English sounds strange to me, also.:worried:

If I hadn't gone today, they would have raised the fine.

Si (yo) no hubiera ido hoy, (me) habrían aumentado/incrementado la multa.

The English is meaningless to me, it is an impossible sequence of tenses. I can only guess that the above suggestion is what was meant.

What about?

Had I not gone to court today, they would have raised the fine.

or

Had I not gone to court today, the fine would have been higher.

Yes, both are OK :thumbsup:

I find the construction "Had I not + pp .." --something that doesn't exist in Spanish-- very useful when simple sentences like this become complex for some silly reason. ;):)

But it does exist in Spanish: Si no hubiera ido ...

The Had I not is a subjunctive, with had = hubiera :)