Yes, I've experienced this many times, with many animals--all power animals for me - some who come for a short while to help me through something, and some who seem to stay with me. Crows are your power animal, perhaps. You should google it and read all you can about crow as a power animal.
I had crow for awhile, may still have them, though I haven't had them come to me lately, so I don't really know.
This is may fave site about power animals:
http://www.shamanicjourney.com/crow-...red-law-change
I looked up crow first, and was happy to also see it says this in the first paragraph-"To have a Crow as a power animal is extremely powerful stuff."
Crows are very intelligent birds. I have always loved crows. Crows are associated with mystery and magic, and changes. They are also known (as I recall) as the spirit messenger, so does any of this ring a bell with you? Are you a psychic medium or have you had any of this type of experience with communicating with spirits? Perhaps this is why crow is w/you? Maybe--or perhaps it is for another reason. So, I would recommend reading many different sites online about crows--and also look on you tube for a documentary on crows. I recall seeing one awhile ago all about crows and it was fascinating! They are an often misunderstood and unappreciated bird, I think and its a shame, because they are truly very intelligent and interesting! They even have a sense of humor (from what I recall in the documentary I saw of them).
Learning about them may answer your question as to why you always see them and why they are trying to get your attention.
Good Luck!