Oh that is unusual, most often than not, artists like you, knew or understand what they drew/paint or about the definition of their art. Since it's a product of subconcious mind, I think the interpretation can be different to everybody. Maybe in time, you will find the meaning of your art piece. ;) For me, when I saw it first time, I thought is a big chocolate marshmallow/mail box hehehe
That would be an interesting mailbox. I am bot sure I wouldn't eat it. But mayne it gives a good smell to the letters. A yummy letter for your taxes.