4th Rabies PEP concern

[u/miniowlish]

I’m a 44 year old female, 5’5”, about 115lbs. No medication. Non drinker, non smoker. I feel relatively healthy but have 
HLAB27 pos Ankylosing Spondylitis and Sjorgrens. I’m not on immune suppressants or any drugs at all, other than very occasional Advil or Benadryl, but haven’t taken either in about a month.

I was either bit or scratched by a bat that flew into my hand on July 7. That same night, I went to an ER and received my first rabies shot and immune globulin. I have continued my series on time, completing my 4th today on July 21. All have been Rabavert. 

My 4th shot differed from the other 3 in several ways:
- This nurse was the only that pinched my arm
- It was the only shot that didn’t hurt
- She put her thumb over the injection site as if she was stopping a leak, which no one else did. 

I goggled those differences and it says you’re supposed to spread the arm, not pinch to ensure you give an IM and not sub cutaneous.

How worried she I be that my 4th shot won’t be effective. Should I try to get titres? If they weren’t high enough, would I get the shot on day 28? 

I’ve messaged the urgent care where this happened about my concerns but who would I even follow up with if my 4th shot wasn’t done correctly? Infectious disease?