Here, have a trigger shot!?

I just got back from my ultrasound. I was so super nervous and not sure what to expect this being my first monitored cycle...I had 1 follicle on each side. The right side was the largest. My lining was a little over 5mm. Which isn't great. I started an estrogen supplement literally as I was pulling out of the doctor's office parking lot. He's hoping it continues to thicken and hopefully I'm getting some estrogen flowing in there in time to help. What I wasn't expecting was being offered a trigger shot. He said size was really good and if I wanted they would call one in and have it overnighted to me. My OB offered to come in on Sunday to administer, but I felt bad and asked if it was something I could just handle. I've got the nurses cell phone number, so she's going to walk me through it tomorrow by phone. I'm excited about trying something new, but still worried about the lining factor. If anyone has any advise on timing after a trigger or on the lining, please feel free to chime in!!

Good thing the husband is going out with a friend tonight, looks like I'll have the whole evening to spend with my good frienemy Google!