I "lost" one lens and later found it (after ~2-3 hours) stuck to my mirror. I cleaned it in solution and put it in its case. The next day after wearing it for ~8-9 hours it slid in my eye and I think it would've fallen out eventually. I was looking at a computer screen at the time and AFAIK the eyes get rather dry when looking at screens. Is it not usable anymore or was it something else?
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Is my contact lens not usable anymore?