I agree with aspects answer, call for angels through God.
I wrote a true story on how Angels saved my life however I know they were send from God.
you can ask for help if you are not sure.
If it seems like you have an Angel and they stay around and try to get a point across they are not Angelic/from God.
If they seem to appear in your dream and tell you something over and over or something to do that doesnt seem right, then it isnt right. Ask our Holy spirit.
Angels will not stay around, they will make their presence known for whatever the message is, they do not draw attention to themselves. Then they move on.
Here is a prayer that I am sure most of us know.
Angels of God
My Guardian dears
To whom Gods love commits me here
Ever this day/night be by my side
To guard and rule
To light and Guide
If they are not from The Lord they are of evil
Our creator makes it very clear we are to serve/worship no one but him.
you will be destroyed if so. (punished)
God will send what help you need. He has send St. Teresa into my life also.