First steps?

Hi Everyone, My other (better) half uploaded my DNA results to some ancestry website. Twenty minutes later, I had a brother and a mother. Now, I've always known I was adopted, it was never a secret and had an adopted sister also. I've thought many times over the years about finding my b-mother but never threw my heart and soul into the process. I tend to keep myself to myself and have a very small circle of friends. I find it quite socially difficult to increase the size of my friend base. Now, it appears that my brother and mother have been looking for me for some time now. So I know that I should not have to worry too much about any rejection. An issue for me throughout life. But, How much will they expect? What should I expect? What do I want? The thing is, I just don't know. I only speak to my a-mother once a week and then for not very long. It suits us, we have never been an over demonstrative family. I know she loves me and she knows I love her. But irregular contact is fine. I even struggle to let my other half in sometimes, despite how wonderful she always is. I guess I'm just terrified of getting swept away. Then reverting to type, and cooling considerably to intermittent contact and disappointing them and myself. What first steps do people take to protect themselves from any potential hurt in these situations? Right now, I just feel all in turmoil and have no idea on how to proceed. I know a thousand people may have a thousand different ideas. But anything may help me start getting some thoughts together. Thank you for any advice. Mi.