music gcse NEA plagiarism

for a section of my free composition i used something that i found on tiktok, it’s like 15 seconds out of 1min and 30 seconds. it’s copied note for note, stupid i know, but i ran out of time. the rest is completely mine and that’s in the middle of my piece nearer the end. will the plagiarism checks pick up on this and will i get disqualified from the whole gcse, just lose that 15% or lose all composition marks including my set brief composition? please help