why are my plants so small??? sorry! (first timer!)

ok i have three plants! they are about 3-4 inches tall. they are going to be 4 weeks old in 3 days. is this normal? they are growing pretty slow. what can i do to help them grow better and faster. just bought some some miracle-gro plant food. its the only thing they sell around here. im going to use it starting tomorrow morning. also on one of my plants the bottom 2 leaves are turning yellow, not the round ones but the ones that grew after them. what does it mean? please help me with my plants! i want them to be good. does anybody have any spare seeds that they can give away or that they want to sell? please let me know! you can always email me at [email protected]

thanx you guys! (and please dont get mad at me if i am asking any stupid questions! i am just a begginer!)

Hey, Look how much sun are they getting and how much water, also...where are you in the world...cuz if aussie its winterish months so thats partially a problem...if your weed is going yellow at the tips of the bottom thats usually nitrogen deficiency, but it can be overwatering causing root rot and stuff, them two bottom leaves are nothing anyway but if it starts spreading ud wanna fix the problem, the way to do this is get some good fert jus a cheap one will do it, but check on the back at the ammount of nutrients, if its to strong ull kill the plant, look through the site or just email me and ill tell ya what they should have...
remember...
never go overboard, it is a weed and if you try keeping it good and doing to much it gets lazy and dies...neglect = best. every 4 days water it and onkly apply ferts 1nce a week...u should only place the fertilizer on the top of the ground soil around the plant then water it and put ur miricle grow on...theyre 4inches, 4weeks...sounds normal for an outdoor thats lacking...ull soon notice new sprouts everyday if you do it the way i have stated.
keep it real and take it easy
Chill out
peace.
PaPPa sMuRf - [email protected]