Kagan on ‘Religious Freedom’- Should I be worried?

First post.
The New York Times just published a piece on Elena Kagan and a memorandum she wrote in 1996 as White House counsel. She criticized a California case which found that a landlord could not refuse to rent to an unmarried couple because of her religious beliefs because California bans housing discrimination based on marital status. Kagan found this ‘outrageous’ and said it threatened the Religious Freedom Restoration Act (later struck down by the Supreme Court).
Beyond the particulars of this case, the idea that people have the right to discriminate as long as it’s for religious reasons disturbs me. Does Kagan also approve of pharmacists right to refuse to fill prescriptions for emergency contraception (or even regular contraception)? Would she allow it only if another pharmacist at the same location could fill the order or even if it was the only option in town? Would she also permit discrimination in housing, hiring, and other areas based on sexual identity if the person claimed it was religion rather than blatant homophobia that was the motivating factor? Not to mention, who decides whether it’s a legitimate religious belief? Don’t forget there are some far-right groups that claim white supremacy as part of their religious dogma, such as the Christian Identity doctrine.
So far, I’ve generally liked Kagan, even if she is more moderate than I had hoped for in a nominee. Nonetheless, I’d like some answers about before she is confirmed.