I think you could fake it with some common lies like "I feel a bit sick" or "I'm having a bad headache" and so on. If someone questions you, refuse it. Make up a something that sounds plausible, like "It's nothing like that. I was just feeling a bit down from work. I'm doing better now, thanks for your concern.". That's all about faking, but I'm curious, do you have someone you can talk to about this. Perhaps not the suicide attempt itself or suicidal thoughts, but just your negative feelings. If you do, it'd be good for you to get it out. If you don't then I'm really sorry about that. I wish you the best.