In all fairness only you can answer this question
If you are happy with these grades then its great and you can continue as you are.
If however, you feel you have under performed then you may need to look at why, but without going so hard on yourself. As it is first year uni is it easy to get carried away with the excitement of the nightlife and the freedoms that come.
Remember it is about finding some balance, get the excitement out of your system, but also at the same time know grades are important if not from a career perspective then from a self achievement perspective, it comes down to the person you are and what makes you happy.
How do you feel about the results you have got in the first 3 assessments?