then I was laid off a month later
Yes. You should consult with an employmment lawyer as soon as possible to make sure that your rights are preserved.
Sounds very promising. You need to have an initial consult with an employment law attorney.
You may have a case. It's important to show a nexus, or connection, between you being "laid off" and being told you wouldn't get a job opening. Preserve your rights immediately and contact an employment/civil rights attorney.
You may have direct evidence to support a discrimination claim based on sex and/or pregnancy. I suggest contacting a plaintiff's employment lawyer right away. There are time limits to pursue claims, and you need to protect your rights, including unemployment and benefits issues.