No worries.
As a point of interest, the Genesis tracks (including special graphics levels) + OhNo tracks come to 27 tracks total. If you can find 3 more tracks, then you've got enough for a different track for each level. There's 4 unique tracks in the Master System version, perhaps you could use 3 of those (or 4 of them and remove one of the other tracks). This is, of course, just a suggestion - it's up to you if you do this or not.
As a point of interest, the Genesis tracks (including special graphics levels) + OhNo tracks come to 27 tracks total. If you can find 3 more tracks, then you've got enough for a different track for each level. There's 4 unique tracks in the Master System version, perhaps you could use 3 of those (or 4 of them and remove one of the other tracks). This is, of course, just a suggestion - it's up to you if you do this or not.