I'm on a low dose (going to be upped next Monday, finally). Two days after my first shot my throat started to feel scratchy and sore. It wasn't until four days later it was apparent I had a cold. But after the cold finally went away, my voice was still lower so *shrugs*. Could be a cold, could be your voice, could be both. I haven't had any dramatic drops, it's been gradual. No soreness since then. But I've heard of that happening. Keep recording yourself and see what happens.