Your grades in the first year are completely downweighted to the overall outcome of your degree. By this I mean that your grades in Year 1 only account for maybe 5% of your actual degree grade, so you shouldn't worry. In fact, my first year didn't at all go toward the outcome of my degree, it was based on an average of scores across year 2 and 3 and my dissertation.
58% is not bad for a first assignment, but you need to speak to your personal tutor and find out what they were looking for, what you didn't achieve, as well as what you did, so you know what you got right and can continue with the positives.
Not worth dropping out over, just put the effort in.