No idea how this happened. I bought some IOTA on Binance and generated a few new addresses in the wallet client so one would reattach. When my balance showed up I copied the adress that was generated into Binance and confirmed. I then noticed that I already used the same address for a transaction from Binance to my wallet. This seems weird to me as I just generated the address 5 minutes before.
Is this fine or should I transfer all my funds to a new seed to be safe?