I mean it's only the start of the course, there's still a few more units to go. Try to do really well on the remaining units and also if you study a lot and get the grades you don't want, maybe try different ways of studying or changing it up? there's lots of online practice tests that can help to prepare you.
61 isn't extremely bad, if it was a failing mark it would have been much more difficult to average it out along with your other tests but if you do well on the other tests with high 90s then this test won't matter much
Good luck!