25-26 is not too old. I go to school at the University of North Dakota, and there are a lot of instructors here who are in their late 20's. I'm not sure about Canada, but at least here in the United States, it's all about total time. Being 25-26 is definitely not uncommon. In fact, I'd say that is the age of most new hire regional F/O's here.

It's not necessarily about how old you are unless you're 45 years old trying to get a regional job, maybe then you'd have issues. So try to get that commercial certificate as quick as possible, get your CFI and start building up your time. Like flyandive said, I know of multiple people who are in their 30's just starting out, and they're going to be fine.

Just out of curiosity, what do the Canadian regionals require for total time and multi-time?