I would say it is not yet a good time to buy. There is a long downwards trend that is continues to be. Until it will not break, I would not buy ETH! It might be, that I'm woring, but I would wait for a safer market condition.
I think it's normal for any cryptocurrency to goes up and down, it's like a roller-coaster or a common proverbial phrase, "what goes up must come down". It means that things change, and if something is increasing or rising, it will eventually decrease or fall. And that's what we always see in the crypto market, it's a normal occurrence.
Btw, the price of Ethereum at the time of writing is $210.65 it's up by a little 0.43%. Is it a good time to buy? Yes, I guess.