Check out this link from today's So you wanna be published site about "I'd be published but I haven't submitted yet." Some very good reasons why polishing your writing is good but eventually you need to just test the water and send something out. Mary gave some good reasons why submitting--even if if means you get a rejection--makes you a writer.
Each month, I send out stories somewhere. Yes, I get many rejections but every now and then --some publisher decides what I wrote is what they need.
If you have something you think is good, why not make next week the week to send it?