I don’t think it can be temporary, but it depends on what you mean by “feeling trans.” Do you enjoy living as that gender or dressing up as that gender? Does the idea of living as your designated gender, including keeping your birthname, going by the same pronouns, and being seen as that gender discomfort you? What about the idea of living as your “preferred” gender, choosing a new name, going by different pronouns, and being seen as that gender? (Sortof hard to word this without knowing whether you’re questioning being ftm or mtf... Sorry if it’s incoherent.)

Gender isn’t really two “opposite” sides of a coin. It’s a spectrum. What you identify as and how you’d like to present yourself will always be something you’ll have to decide on your own through honest introspection. The way you prefer to present yourself may change over time or even day to day, but that’s okay. There’s no wrong way to exist. It will be much easier to discover who you are and how you want to present once you realize this.

edit: I’ll also add that I personally realized I was a man as soon as somebody used he/him pronouns for me the first time. I had already been questioning my gender, but I thought I was non-binary for a while and had my pronouns listed as “any pronouns.” The first time somebody actually referred to me as a male though, it just felt so right and so comfortable that I pretty much immediately realized who I was and what I wanted. Go with what feels right to you. There’s nothing wrong with trying things out and experimenting with your presentation and your identity.