At at my university (UCL) it is the consensus that, comparatively with A-Level Psychology, degree-level Psychology is not enjoyable. We spend most of the time writing lab reports in ridiculously scientific language for an experiment which goes something like: Wait for an hour whilst your participants sit at a computer pressing a key every time they see a dot on the screen. If you enjoy making something scientific for the sake of it, and making discoveries which mean nothing at all and were probably due to experimental error, then go ahead and do Psychology. But then again your course may be more interesting if it's not BPS-accredited.
I would encourage you to think about whether you *really* do enjoy Psychology, or you just enjoy it marginally more than English. For example, would you choose to read a University-level Psychology textbook over say, watching a movie/going out with your friends? If it's the former then by all means study Psychology because you probably do have a passion for it and will greatly enjoy your 3 years studying it. But take into account that you won't be able to study it to PhD level because it's not BPS-accredited (not 100% sure if this is true...), and it may not be much use in getting a career in something Psychology-related either (such as counselling or working with people with psychological problems).
If I were you I'd do the more respected course (unless it is really dreary, and imo English and Psychology are pretty level in terms of dreariness), which seems like English in this case. Most university courses are not exactly fun, so you may as well do the option which will give you the best prospects. Both English and Psychology are fairly generic courses (although I think Psychology has slightly better employment rates) which will allow you do your 3 years and then go into a career you will enjoy. Do you have any idea of what kind of career you would like?