Try talking to mother again????Advice???

Any advice????? I talked to my german birth mother twice. I was adopted with my brother from a german orphanage in 1968. The first time I talked to her she wanted pictures and I sent a long letter, etc. The second time she said it wasn't a good idea. This was in 95 or so. I know there is an older sister and my father was an American GI. If I could only get a name. Should I try again. I'm terrified but determined.