Upgraded to Yosemite with Existing SSD and Trim, is Trim On?

I had a computer running Lion (Mac Powerbook, Early 2011) that had a third party SSD (Crucial MX 100, 512 GB). I had used Trim Enabler 3.24 to turn on Trim for it.

So then I upgrade to Yosemite (my institute doesn't allow El Capitan yet). It is working fine. I'm guessing that Trim is still enabled, but I'm not sure. To complicate this, I understand that Trim Enabler 3.42 modified a system driver? Yosemite allows Trim to be enabled by a terminal command or by Trim Enabler 3.4 or Disk Sensei. using a kext certificate?

The terminal command presumably won't tell me if Trim was already enabled?

Can the new programs that enable Trim with the kext certificate check if Trim is enabled by modifying the system driver?

Do I have to worry the enabling Trim twice will mess something up?

How do I check if Trim is enabled?