Leeza1007,
Don't worry about what strain it is. First off, unless you bought from a top-shelf distributor who uses pedigree to sell his inventory, the street distributors are going to call it anything they want. Secondly, within each strain there can still be a lot of variance, so any one of the seeds grown from that plant might in fact end up a little different from that plant. No two tomatoes are exactly alike, though they can be very uniform.
If you're concerned that you're going to LOVE this plant's smoke and will never be able to get it again, then take a cutting, make a clone and put it back into veg by putting under lights for 24 hours a day and keep it like that. I've never done this personally, but you can research it or ask in the Advanced Cultivation forum.
Otherwise, when you smoke it, it might have a particular taste that will help you narrow the possibilities, like lemons or pine needles. Then you can start buying weed with that profile until you find something you think is really similar, and call it a day.
Welcome to growing!