If not, can see how it would be unsettling because as best I can tell, you’ve not had female friends for four years and one appears via a call.
Do you know if your GF and/or those near and dear have experienced a significant other having a friend. with whom they become romantically involved or if one or more of ’em have been the friend with whom things went further?
Does this strike you more as a blip, a one-off or has she said and done other things that reasonably suggest an unhealthy level of insecurity and need for control?