Do you think that it is better for me to do biology or biomedical sciences at uni?

I absolutely agree. "biology" from what i have seen my other friends study at their university really differs. I am a student at manchester university doing an MSci in Biochemistry (third year), and in comparison we 7-8 courses in chemistry throughout the degree. My degree is also a lot more flexible than other Biochemistry degrees. Even up to third year, I still had a wide range of freedom of courses I could pick, some of them closely related to biochemistry, some of them less so (e.g. Pharmacology, I opted in for every optional Pharmacology course I could). You can have plenty of opportunities to study your favourite subjects in a more well rounded degree with plenty of optional choice units.

When you said you loved biological molecules I thought Biochemistry would really excite you. However, I think its also important to realise that your undergraduate degree doesn't necessarily tie you down to what you will have to do for the rest of your science career.

From the courses I have taken so far:
Anatomy: I found the anatomy very boring in my anatomy and physiology first year unit, its a lot of memorise and learn. However, human physiology was interesting. I found human physiology the most like my A-level biology course, there weren't too many new difficult things to get my head around, just often the same concepts but in much more depth.

Evolution: My first year evolution lectures were soooo interesting, but at the same time difficult for me to revise. Its a very story-like narrative, which makes it difficult for me to memorise.

Pharmacology: Is realllyy good. I found learning about clinical trials and drug development really interesting. The only thing about pharmacology is that you have to not be afraid of maths. There are some complicated mathematics in the binding of drugs and their effects etc. And also some odd concepts, which take time to come around to. It didn't put me off, but it was definitely a hurdle at first. Also, I think the people who started on a Pharmacolgoy degree, rather than a more broad biological science degree, has much less choice options. They couldn't pick their practicals with as much freedom, they had a dedicated labs module only for them. So be sure if you were to go for pharmacology, that you're 100%.

The other things you said you liked I haven't chosen to do (but I could have, in my first year). I agree with immunology, its really complex to learn too. Microbiology was my first year optional, I found it changed my perception of everything, but we will agree to disagree haha

I remember being in a similar position in year 12. I just knew i liked biology (and chemistry) and that was it. What drew me to manchester, and biochemistry, was the freedom of being able to change degree programme up until year 2. Some subjects you don't come across at all in a level (like pharmacology etc) and you just won't know until you try it and see if you like it. Pick it as an optional unit, then if before the end of year 2 you realise you only liked doing units from a specific area of science, then you could switch.