Yes, that can absolutely cause it.
If you were my student, I would ask you for your original draft. You should have the draft that you gave to AI. If you are telling the truth your first draft should be 100% human written and clearly so.
That can prove you just used it for spelling/grammar checks, and satisfy your lecturer.
If you don't have a human written first draft? I'd presume you are lying.
In the future -
1, Save your drafts if you are going to use AI for checking,
2, Check your class/university policy very clearly for permitted uses. If they don't have a policy, ask your professor/lecturer
3, When you give AI your writing, be very very clear say something like this:
"Please fix the spelling, grammar, and punctuation of this piece of writing. Do not alter the word choice, style or structure"
That usually results in it just making basic fixes.
If you don't tell it not to, it will often make bigger changes to your writing and style, which can then be viewed as AI-written.