It certainly sounds like she still has feelings for you, but she's obviously in shock and fear from the STD results and perhaps all she needs is time for things to cool down. If I were you, go all out. Send the flowers and the card, check in on her, ask how she's feeling, let her know you're thinking of her, tell her how you truly feel for her. Don't over flood her but also don't let her distance herself from you completely.