MIL issue. Feeling sensitive

For the last year and a half only my mom, and my 2 SIL's have known that my husband and I have been TTC. Since we're starting the infertility dr visits this month, I decided to tell MIL. She's a nice person, and we get along btw. I sent a heartfelt email about it, mentioning that We may need some understanding and support in the next months. 5 days later: no reply, no call/text/email. And this is why I don't tell many people. Am I being too sensitive? What should I do now? Any similar experiences?