I don't know if its a bug or not, but I truly think something is wrong. I understand the game is based off of RNG, but the last few days with running only 250% Rares, I get some great stuff throughout the days (including multiple 13* weapon drops). This morning I saw I was able to do the Cradle EQ and so I used the 400% Rare I had bought with AC. I played with it throughout the day doing SHAQs and EQs (including the Dark Falz we just did multiple times) and still have yet to get even a 10*. I know 10*s aren't all that rare, but it would have been better than all the blue weapons and purple armor I got all day.
Edit: I had it this morning until maintenance and when I came back from maintenance, I still had about 111 minutes left on it.