I took the leap and took on a U2...question and support please?

I am new to this board as I post only on the macaw board. After much thought after losing my Senegal I felt that another bird should join my family. Birdman told me about what could happen if I was to add another bird and I tried to weigh all the pros and cons out before getting this U2. I just personally feel that a parrot is first and foremost a flock being and therefore I just can't keep one as a solitary pet only.
Last night I took on a five yr old ( that could be questionable ) female umbrella named Pearl. I am her fourth owner within this time. The last owner had her only for 10 days as her husband had a very bad allergic reaction to her.
I realize this is the "honeymoon" stage but she does seem like a real sweetie. She is plucking slightly (just one tiny bare spot so far). But she definitely is over preening. Unfortunately she has been on a seed diet, but did eat pellets today here. She also didn't have a night cage and I don't think she was getting a proper 10-12 hr uninterrupted sleep. I am taking her tomorrow for blood work to rule anything out medically. I have a question about a behaviour she is exhibiting that I haven't seen before in a parrot. Maybe someone can help me out with this? The only way I can describe it, is to make a comparison as to a horse cribbing. She opens her mouth and holds onto the bars and shutters her wings out to the side, while making this kinda gulping noise. She does it over and over. I had left her out of the cage all day and she is doing this to the sides of the cage or she will go in and do it for a bit and then come out and repeat it.
Anyways, thanks so much in advance for any support you might have to share

If you can get a video of it I can tell you more but it almost sounds like a mating thing she is doing. IF she is doing what I think she is doing, then you better be real careful where you pet her and be cautious on what she does. A hormonal too is nothing to mess with unless you want to get bit. And don't ever allow her to get on the floor. Most U2 I know are floor territorial including the one I had.

Thanks Micky, but it's not a sexual thing. I believe it is a stereotypic behaviour stemming from being locked away in her cage for many months or possibly years. I was able to contact the second last owner that had her for six months. She informed that the women she got her from never let her out of the cage. Only a couple old wooden toys were in it and terribly terribly filthy. That women said she rescued the bird from a abusive guy. This woman told me that it took her weeks and many hours of trying to pry her off the wires to get her out of her cage. I have a video but don't know how to upload it.
Thanks

You can upload videos onto photo bucket or Youtube. Then you can post the links here!

If your rather new to U2, why such a knowledge on knowing it's a stereotypic behavior? Once we see the video we can give you more insight! Have you ever seen a Cockatoo do a mating behavior?

[ame=http://youtu.be/JrT89JpSIk0]Pearl - YouTube[/ame]

Yes it is a regular Cockatoo behavior, nothing unusual!

Especially in too's that are caged a lot