When will Euro rates go down?

No one can surely tell you when Euro will go down again. If you ask me, I will tell you Euro will go up this month as US dollars is already too strong. The value of US dollars is already exaggarated.
Please DO CHANGE your money in Hong Kong. Hong Kong dollar is only a piece of rubbish in Paris. The exhange rate is very very very very very low and only a few exchange bureau will accept Hong Kong dollar. You can change money in any banks in Hong Kong. The rate is 100% surely better than in Europe.
You can also withdraw money by your ATM card in the ATM machine in Paris. It's an easy way to get Euro cash as well. The rate is similar to change money in Hong Kong.