Not right now. I've got a lot on my mind.现在不行，我没心思。

...have got a lot on my mind …有很多心事。例：I've got a lot on my mind. I have to take the final exam in two days.我有很多心事，两天后我要参加期末考试。My girlfriend just left me, so I've got a lot on my mind.我女朋友刚离开我，我心里很乱。