Grow your own food.

First let me start by saying sorry I havent posted in some time this is due to real life getting in the way!
I have been reading other peoples topics on what there gardens are or have produced.
An I sit here quietly keeping my fingers crossed that my first try at growing something wouldnt be a total disaster.
Well as you have probably guessed it has gone quite well so far.
I bought ( yeah i know i didnt grow from seed ) 3 tomato plants each was no more then
4" in height.
Each one was planted in its own container when they grew enough.
2 were planted in horse manure and placed on the ground.
the other one was planted in some old potting stuff i found in the basement ?
no idea what it was as the bag was ____ .
well the 2 in the manure are growing alot slower then the other one but all flowered and have small tomatos on them.
I did think i had killed them all off as a surprise frost came one night an they had already been put outside.
I think this is why they are growing alot slower then the other one.
Ive already saved the seeds from what I have taken off the first plant so I have seeds for next year.
Well that is if they can be reused ?
Anyway hopefully if i do this correct you will see a pic or 2 of the big plant that has already given fully ripened tomatos.