I've moved on to Level 2 IT/Computing subjects now, and most of the students have done M150 previously - and you're certainly not the only one to think like that! Personally I quite enjoyed the JavaScript parts, but there are a lot of people on my courses now who absolutely hated it.
Don't forget that it's only a level 1 course, and you only need 40% to pass, and please don't forget about your tutor! They're there to help. Have you been to any of the tutorials? You might find them helpful, since in my experience it's often the other people who are struggling who go to them. I think my tutor ran at least one focusing on JavaScript queries when I did M150.
Start off very very basic, just try to do a tiny part of the question/activity and check to make sure that line was processed correctly. Build it up slowly, checking every couple of lines - then you can see exactly where you're going wrong and read a bit more into that part. Also try looking at the solutions to some of the activities, typing them up and editing them bit by bit to make them do something different. It might help you understand how it works.
Luckily for your final TMA, you can choose between a JavaScript question & a report question!