That is actually a really good offer as far as getting paid to be trained. When I became certified a little over 4 years ago, I was only paid $6.15 an hour while in training. Then once I became certified I got a $3.10 raise to $9.25. The pay was horrible for the amount of work I had to do. I am curious, where do you live? Around here it's a fantasy to get paid $11 an hour while in training! I live just outside of Philadelphia. Healthcare workers receive good pay around here, but as with most cities, CNA wages are horrible.
That choice is up to you, and I am sure you have since decided already. You want to weigh the pro's against the cons. If you decided to go to the CNA training, I hope you left your current job under good circumstances, just in case you decide to return. If the pay was better, and it's something I really wanted to do, I would give it a try.