You are welcome to continue using the visa until its expiration date, but remember that you will be checked at the border by a CBP officer, who will make the final determination as to whether you are admissible to the US.
In general, crimes that will make you inadmissible to the US involve "crimes of moral turpitude" (such as murder, grand theft, etc.) when sentenced to prison time, crimes involving controlled substances, along with sex trafficking, money laundering, terrorism and things like that.
If you only received a fine for whatever it was, and it was not regarding a controlled substance such as cannabis, then it's unlikely to affect your eligibility to enter the US.
When you apply for a new visa, you will have to disclose the new criminal conviction, and the consular officer will advise you if this makes you inadmissible to enter the US, and whether (and how) you can apply for a waiver of inadmissibility. If the crime would normally make you inadmissible, but you receive such a waiver, you can still travel to the US.