Is it okay to leave a question mark at the end of this sentence?

Education & Reference by Anonymous 2018-09-03 10:47:03

Social Science

No response

"After a brief chat I don't believe I have particularly severe ADHD, but perhaps may have some symptoms?" I sometimes see people type/write like this and I think it sort of helps express that the writer is unsure and is not making a statement. Or would this be an inappropriate? Too informal?