first round of Progesterone shots today 😩 help!!

Jessenia • Mommy of 3 girls ❤️
Doctor appointment today and i get my first shot..😲 im scared because i hate needles but gotta do whats best for baby ❤️ 
Has anyone else got them and they are successful? Do they hurt ? What should i expect? I am 16 weeks 4 days pregnant 💕