I understand you exactly and you are completely right to think that maths is hard, because it is! It's the second hardest a level you can do. And even those who achieved amazing grades in GCSE are failing at maths currently, so if you feel like you won't be able to cope with it then you're wise not to do it. However, i'm not here to tell you not to do a subject or degree. But the issue is if you want to do electronic engineering, then yes, you will require maths, and at a decent level, whatever happens.
Maths is not impossible. Those who put the time, effort and more into their study's, especially maths will have a better understanding of the subject. You just have to think hard, and focus. Look at what they want you to work out and how you're going to get the right answer. Trust me, if you motivate yourself to work hard, do extra hours of maths study, focus and contribute in class, and even get a personal tutor, you will get the grade you want.
There is an alternative however. You could stick with the subjects you want to do and then if you feel you want to do a degree in electronic engineering, then you could do that course with a foundation year. Usually this foundation year is for students who didn't achieve the right grades at A Level or just picked the wrong subjects. In your case, you would definitely need maths, but you are doing 2 hard subjects which will increase your chance of getting a place on this course.
The only issue is that the foundation year is going to cost you money as well, sometimes up to £8k
Only you know how good you really are and if you want to pursue a degree in engineering, then work hard!
Any questions feel free to ask