I would write in the 3rd person in introduction but the rest of essay from my point of view in main body.
This is an interesting idea, and it could create a nice effect.
In APA style dissertations, the writer usually does not use first person. John Cresswell (2008) says qualitative research can involve first person but quantitative should not.
In a university essay about what YOU have learned, I really think you can use first person. The other option is to write about "the student" but that would be confusing. It depends on the professor! Ask her. But really, I think for this assignment first person is okay.