So I guess I'll elaborate since a lot of the comments above aren't super helpful. Your plant looks fine. Is it kinda small for 2 months of vegging? Sure. But that could be genetics (which you don't know) or the amount of light it gets based off your geographic location (which we don't know) which effects hours of sun light, average temps and humidity etc., or it's actual physical location (ie. Is it getting full sun all day, part of the day, in the shade etc.).
Your also not hammering it with nutrients like a lot of established growers, so it's not going to grow as fast. A lot of the commenters making statements regarding it's size at 7 weeks, or saying it looks like a 3 week old plant, whatever are comparing it too a plant that has been grown in strictly controlled environments rather than in nature, where marijuana grows much slower and more eratically.
My advice, if it's not in a potting mix with time release fertilizer (which is junk btw), is to start feeding it some nutrients at a very low dosage. Organic tomato fertilizers are good if you don't have access to weed specific nutrients. MegaCrop is giving out free samples, so you can Google them. Haven't tried it yet, but a lot of folks on here love it. Also you may want to transplant it to a bigger container soon, preferably something at least 5 gallons, but the bigger the better.
Otherwise, keep doing what your doing. It seems like half the newbies on here are drowning or burning their plants too death within the first week, so I'd say your kicking ass so far.
Oh, and as always, if your serious about this as a hobby, read everything you can find. All the grow journals on here are great sources.
www.growweedeasy.com is also a great place to go.