Hello! My name is Mona and my chihuahua is behaving exactly the same like yours for some time now. It was allways hiding but, after few minutes she was ok. For 3 days now, she does not eat at all by herself and she is hiding under blanket, furniture or courtaind. She is 1 year and half old now. I wend to doctors and they have told me that can be a fobia of some kind or a psihical trauma. I’m terrified!!!! Did you found out what caused these hiding? Thx!