I recently had a very nice phone conversation with a potential employer. She later sent me an email asking best dates/times for face to face interview, as well as some references. I emailed her the requested information. It's now 3 days later, and I've yet to hear back. Is it too soon to send a follow up "Just making sure you received my email"? Or should I give her another day or two?
No it is not. If it has been 3 business days, if I were you I would send an email now asking if there was anything she was waiting on me for. Assuming you spoke with an HR, it is not unusual for an HR to overlook/forget about candidates who are still in the initial phase. Similarly, it isn't unusual for the HR to receive reminder mails from candidates. Just a pleasant 'Hey, Regarding our conversation and email exchange the other day - I was wondering if you need any more documents/information from my side' should do. Good luck.