The problem with 'cashflow' in English is that it has a business meaning (which I think is income generated from a business or investment) and a colloquial meaning (referring to liquidity or general financial situation).
If you're looking for an equivalent to the business term, I think キャッシュフロー is probably ok. But if you're just trying to refer to your impecuniousness in a mock-business sort of way, you should look for something else. キャッシュフロー hasn't made it into ordinary Japanese vocabulary in the same way that 'cashflow' has in English. I might suggest 金銭状態 as a possible equivalent, but there are probably snappier and more appropriate ways of saying it.
Note: I just thought of the expression 金回り, which might also fit the bill -- although 金回り could suggest a rather more serious situation than the casual use of 'cashflow' would imply. At any rate, this page (http://thesaurus.weblio.jp/content/%E9%87%91%E5%9B%9E%E3%82%8A) gives a lot of interesting synonyms for 金回り that might be useful:
収支 ・ 財政状態 ・ ふところ具合 ・ 台所事情 ・ 金繰り ・ 資金繰り ・ 金融（調査） ・ （金の）流れ
羽振りがよい ・ 金がうなっている ・ 潤っている ・ 金持ち ・ バブル（紳士） ・ 潤沢な資金をもつ～
経済的苦境（にある） ・ 手元不如意 ・ しけている ・ 苦しい ・ （台所は）火の車 ・ 金欠病 ・ 金詰まり