I just recently submitted my application for UK Tier 4 Visa and I realised I might have made an error that could be damaging to my application with regards to writing an accurate description of my purpose of visit to the UK in 2014. To begin with, in 2014, I visited the UK on a Student/Tourist Visa for 4 months (student/visitor visa allows one to stay up to 6 months). The exact purpose of that trip was to visit a university professor and talk about research projects and at the same time I did some work on a personal project that both the professor and I agreed on verbally on my own personal capacity at home (i.e the place I stay near the university). Note that I was not at all affiliated, paid or was under any kind of contract -- the whole thing was an informal interaction with the professor.
Now, in my application, I noted the purpose of the trip was "Volunteer research assistant at the [name] university". However, I realised now that this sounds very misleading in the sense that I might have spent my time in the UK as an unpaid worker which is not permitted. Now, I am very worried that my application will get rejected base on a narrow interpretation of my statement. Is there anything I can do about this? Note that I have travelled in the UK after that year and the UK borders did ask me about my 4 months stay and they were OK with it since I was able to explain my true intent of my visit.
As I have said, I felt it sounded dodgy because it sounded as if I worked in the UK as a unpaid worker which is really not true at all. I simply visited the professor in the university and discuss about a project that we can work together but of course, I was not funded for doing it and I funded my own stay at the university. I simply ask if she can propose something so that I can research on it on my own time for my own personal development towards academia. I stay in the UK within my time limit so that I can interact with her during her office hours while I work on the project at my own room that I stay near the university since I was not at all affiliated. The thing was I was trying to summarise what I did in a few words, and I did not know how to describe what I did and so I thought "volunteer research assistant" but I later realized that it could mean formally as unpaid work and can claim benefits etc. which in no way I have access to these benefits. I think a better description would be "visiting Professor at [name] university" because I am not at all affiliated with the university and this is key. Anyway, I would like your thoughts on this matter.