Well what's done is done....
However; consider meeting with your advisor and talking about the situation.
Do not know what year you are in nor the pre-requisites for the composition class.
May have been a mismatch in taking a class that you were simply not ready to take.
And for composition the topics are immaterial. How well you can write is what counts. Or should count. Ignore the topic per se. Does make it more difficult when writing about things we do not know or are not interested in. Yet that will happen in most career settings.
As for timed, under-pressure writing - would not expect that unless you are in some sort of journalism program and may truly need to write to hard deadlines. Especially to keep your job.
Meet...