Hello. I Had A Problem With A Stopped Up Drain.

Hello. I had a problem with a stopped up drain. It wasn't draining at all, and I poured an entire bottle of Draino Max Gel into it. After leaving it sit, it didn't drain at all. I then gloved up and opened a fitting to let the water drain out (across a concrete basement floor, to the floor drain). I continued to run water through it to help flush any of the chemicals from both the drain and the floor. This was about 2 hours ago. Now I have a very sore throat and throbbing headache. How concerned should I be?