You used a lot of awkward repitition:
I had one before.
But I've known that before
But we've had those before.
This is too short of a poem to use so much repitition. Also, the last line:
You talk quickly.
I've heard poems end like this before, but I don't really like it. It leaves the reader, me, with a sense of something incomplete and obvious - we understand the fast talking already (hence "fast mouth" is the title). I'd revise some of this.
Points: 890
Reviews: 688
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