Just to add

I simply want to add the field service overseer usually makes a mental note of any special interested ones and may assign someone to make calls. They usually don't keep written records unless you are considered a formal Bible study and in that case a brief record of your name, address and publications studied is kept.
You may be considered a "special" interest because of your association with your friend.

My guess is that your friend made that arrangement herself with the field service overseer to have someone call on you.

The reason you may have different ones calling on you is because they will try to find the witness that is the most effective with their calls on you.
The person calling on you will usually jot down what was discussed with you, what was placed and how you reacted and will get advice on how to proceed if necessary.

As a JW I've gone through this whole process a number of times.