Professor not responding to LOR email after initially agreeing My situation is a bit tricky, and I'm not sure if I'm reading too much into it.

I asked for a letter of recommendation from two professors at my university. They both replied yes to the initial email. After about a month, I sent them another email with my personal statement and resume attached, and told them the deadline. I asked them to let me know if they received everything, and if there's anything else they need. One professor responded immediately saying he got my email, but the other professor still hasn't responded 5 days later. 

I am worried, because the second professor usually responds very fast. Also, the email I sent necessitates a response, so it doesn't make sense for him to not respond to it. I don't know if I'm overthinking this, but I accidentally called this second professor "Professor" in my email even though he's technically a lecturer so I always address him as "Dr. So-and-so" in my emails. I copied and pasted the email content from the first professor's so I forgot to change the title from "Professor" to "Dr." I'm not sure if he would necessarily take offense at this? 

Any recommendations? Please let me know your thoughts! And thanks in advance!
I'm not sure if I'm reading too much into it.


I think you are.

My guess is that Professor #2 received your email, saw that it contained information for your letter, remembered that he had already told you he would write the letter, and set the email aside, planning to read it in detail when he got around to actually writing the letter.  He probably didn't read far enough to see the part where you asked him to acknowledge the email.

So, if you're concerned, simply send a second email:


  Dear Dr, #2,
  
  I just wanted to make sure you had received my email of August XX with the information for my letter of recommendation.  Please let me know if it looks okay, or if there is anything else you need.  As a reminder, the deadline to submit the letter is October XX.
  
  Thanks very much for writing a letter for me!
  
  Sincerely,
  
  Lily


As to your other question:


  I accidentally called this second professor "Professor" in my email even though he's technically a lecturer so I always address him as "Dr. So-and-so" in my emails.


Don't worry about that.  It happens all the time and most professors eventually just stop noticing.  It's certainly not the kind of thing that would offend someone so much as to affect their decision to write a letter.