Hi Grey Cat,
Always a tricky one, but it's really important to be on the right course - as a university lecturer and former head of student support, I've seen so many students in tears (and an academic mess!) due to making the wrong choice for them.
So firstly keep pestering re: the transfer - don't be too much of a pain though as they may not be quite as willing to be 'helpful' if you're stalking them down corridors (I've experienced this!)!!
But do maintain that level of interest, and ensure your real passion for 'mechanical' comes through, ie. this is about passion for the subject and essential to your career path* not just 'studenty' indecision.
*Do have a chat with a careers advisor too - both to explore other 'ways' into your chosen career and to perhaps discuss whether sticking with 'electrical' would have an impact on you getting into a more 'mechanical' career, as it's often the core skills you develop as a student that are more important to an employer. I know you said you're getting grades in the latter, but is this re: the subjects or a skills issue that you could get help to address?
Yes, I agree with your thinking on the 'stick with it' for a couple of weeks - you might find you enjoy it or it might be possible to transfer then if someone on 'mechanical' leaves - but do be wary of any transfer deadlines: at our uni, you have to be in class by Week 3, so could you perhaps attend some of the 'mechanical' classes in the first couple of weeks too (best to get permission though!).
And finally, look at other options - could you go elsewhere to study it? Could you get a job/apprenticeship and study part-time (there are often more part-time uni places than full-time)? Could you work full-time for a while to build your CV and reapply for the course for next year? Between your tutor and careers, you should be able to discuss all these options in full.
Hope this helps? Take care and good luck...Helen