Guy's Behavior

Deep red scratches on his back?

I work away. I came back last Saturday and spent the night with my b/f. He admitted to taking cocaine the night before. He had scratches on his back - three thick bright red scratches on either side of his lower spine. Not random. Three on each side, not scratch lines from bleeding but they looked very like square finger nails had made them to me. There were a few lighter ones to the lower sides of his back too and a scabbed over thick cut on the right lower back. I asked about them and if he's had sex - he replied 'I wish' as a joke but then said he didn't know how they got there. A few days later I mentioned it again as the freshness of the scratches suggested it happened just before I say him (maybe the night before) and he said he remembered that he'd tired to scratch himself with some metal tweezers. I think this is nonsense. Gaslighting or likely truthful? Tweezers wouldn't make thick marks like that and the positioning meant they were done once and really hard on the back. Scratching is more irregular. Is it just me or is he a liar. I think I know the answer but could use some male thoughts (kind ones) please?

Deep red scratches on his back?
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