Supp. Recs help!

<p>Quick question guys:</p>

<p>I know I am getting 2 recommendations from teachers in academic subjects, and one from my guidence counselor (those are required).
HOWEVER- the teacher that I am closest with at the school (who has not taught me for an academic subject) is writing me a STELLAR recommendation, and so I am including that as well.</p>

<p>THE PROBLEM: I already have 1 supplemental recommendation, but this summer I did reserach as an intern at Columbia, and while I did work directly with a professor, I don't know how WELL the professor got to know me. I do reserach at school, and so this recommendation would tie into my interests. But, I don't know if she will write me an EXCELLENT one (b/c idk if she knows me well enough) and also I don't want to inundate the schools with 2 SUPPLEMENTAL RECS!
I understand that schools have over 20,000 apps to read, and I dont want to put in an extra recommendtation that might not truly enhance the application.
Thoughts???</p>