100% do psychology. I was in the exact same position as you, then I chose to take maths and psychology at alevel, even though i did well in maths at gcse (i got a 7 (a)), i dropped it within 3 weeks. maths at alevel is ridiculously fast paced so if you can't keep up ow you will have an incredibly hard time at alevel. taking something you hate will not only be time consuming but may also dampen your motivation to do well in other subjects. psychology by far has been one of the decisions ive made, it's stilla. respected subjects even though it is nowhere near as hard as maths. i also don't know what i want to do at uni however at most of the unis im looking into, and keeping in mind im looking at prestigious universities such as lse and kcl, consider psychology as a science. maths will be no use to you if you don't want it at uni, which im assuming you don't want as you hate it anyways. even friends i have now who got a 9 at gcse (equivalent to higher than an A*), are struggling with a level maths.