Some old-timers are still shy of using contact forms on websites. Realizing that, many Providers include their email address on their websites, too, as your's did.  (Sometimes they only add a direct email address after posting to TER Newbie or General: "How come nobody is using my contact form?")
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Search Newbie for "contact form". Here's one old thread:  
http://www.theeroticreview.com/discussion-boards/newbie-33/historical-reasons-159579?frmSearch=1#159579
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I don't see any problem with contacting her via her website form. I don't use contact forms, but if I did, I'd mention the previous email so she knows that I'm that same person.  
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Another old frequent topic (use the Search button) had to do with the basic "How long should I wait?" Q.  Some Providers have a busy REAL life. If she is college age, maybe she is busy shifting from her school schedule to her summer schedule (moving, vacation / traveling, visiting home before starting a summer job).  
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You just have to carefully tread the unknown fine line between expressing interest and becoming annoying or worse (stalkerish).  Be patient.  I suggest using the contact form now or soon.  If no reply from either, wait another 7-10 days and try one or both methods again.  
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(Geography component: Is there anything going on your/her area that would distract her for a while? Tornados? Fires? Floods? Some annual event where "Around these parts, everybody stops work and goes to the X Celebration for the whole week!"?  Account for that and adjust my "7-10 day wait" figure before sending your 2nd email.
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Good luck!  

I just don't like them, they feel so impersonal and like I am "applying" for a date. That's the reason I don't use them, after all these years I simply don't do anything that "feels" like i am jumping through hoops. lol

 
That said, as long as "you" don't mind using them, my feelings on the subject don't really matter, and it is a fact that some providers only respond to inquiries made through their contact form. I don't see any reason in the world why you shouldn't reach out one more time via her preferred method of communication and then you have to accept what you get. Either she will get back to you or she won't and "bugging" her further won't have a positive influence on her. Keep in mind that three days is not really that long a time for many providers, she could be busy, she could be touring, she could be on vacation, or your email could have possibly gone into a junk folder. I would most definitely give it "one more try" before writing her off.

Some ladies have contact forms and do not review them often enough. Same for email. If they publish both the use both. Just be sure to include a note in each that you also sent a request via the other one, just so she doesn't think she's getting a duplicate request.

... and her profile says “Contact through P411”, try doing an appointment request through P411.