Boss asked me to change my scan date

Alex

My boss pulled me into the office earlier to tell me I have to change my 12 week scan appointment which is in less than a week because his wife has a scan on the same day because they believe she's having a ectopic. I understand what they are going through but honestly I think it's selfish for him to expect me to miss my own first scan for his convenience. By law I am entitled to have my medical appointments regarding my baby. What do you think about this? It's actually upsetting me