Run a test only cycle first if this is your first REAL cycle. A min of 500mg of test is suggested, anything less is a waste of both time and money....not worth shutting your own test down for a mere 250mg a week bro.
If I was you, I'd probably wait and continue to go natural for another few years. At 6'2, you should have more than 170 lbs. on you. Eat more. Good luck making your decisions.
That's the thing I'm having a hard time gaining weight, even taking 4 weight gainer shakes a day and having a strict diet. I get well over 4000 cals a day. I want something where I can up my weight 10-20lbs
4000 cals a day is not enough if you are trying to gain weight/mass, especially with your stats at 6'2 170lbs. Up both your caloric and protein intake. With your stats and goals, I would suggest taking at least 6000 cals a day and 340gr of protein (2gr per body lb.). Do this right and you can put on a solid 10-15 lbs of LBM in a few months time.