I’m terrified...

So, I’m a hypochondriac and have horrible anxiety. A month ago I discovered a tiny lump in my breast, went to an urgent care clinic and they said it was fibersistic breasts. Sorry if that isn’t the right spelling. I was content with that diagnosis. The lump didn’t hurt and still doesn’t. About a month later I discovered I had multiple lumps in both breasts. I went to my actual doctor and she said she also felt just the fibersistic stuff but said she was gonna schedule me for a basic mammogram just as precaution and I’m scared to death. I’m only 21 and there haven’t ever been any cancers in my family. Has anyone else had this?