Youngs required keyhole surgery at the end of June after damaging his knee in a wrestling bout with England team-mate Toby Flood.
The Leicester scrum-half missed all of England's World Cup warm-up matches but returned to action with a bang against Argentina last Saturday.
Youngs came off the bench to change the game for England and he scored the decisive try in a 13-9 victory over the Pumas.
England face Georgia next and Youngs is in line to start his first Test since the defeat to Ireland at the end of the Six Nations.
"When I first did it, it was a little bit worrying,'' said Youngs. "Luckily I have great guys who were there. As soon as I knew the target was to get fit to be here at the World Cup I knew I was good to go.
"I went through some pretty gruelling sessions but it's all for a good cause.
"I've been fit and ready to go for a couple of weeks now. I was chomping at the bit at the weekend and happy to get on. It was just nice to get back in the swing of things.
"I feel as sharp as ever. I feel really good. If I get to wrestle Floody again I'll certainly look to dominate him. I'll grab his ears and chuck him out the ring.
"The mental side is probably the hard part, being tackled for the first time after surgery, but as soon as you get that out the way you know you're good to go.''
Youngs was sent on against Argentina to inject some pace into the game and he did so with his first touch, taking a quick tap penalty, before scampering over for the decisive try.
"That impact is what you want,'' said England manager Martin Johnson.
"To come on in a difficult situation and play with that composure was very good.''
Youngs' previous Test appearance was arguably his worst and it ended in bitter disappointment as England's Six Nations Grand Slam ambitions were wrecked by Ireland in Dublin.
It was an afternoon of painful but valuable experiences for Youngs, who is determined to emerge stronger for it.
"I've had my highs and I've had my lows but it makes you a better player and a stronger player,'' said Youngs.
"Obviously Ireland was a poor performance by me and a frustrating time.
"At the same time I learned so much from it. At the time you are absolutely devastated but you look back now and think it put me in a real good stead and made me address things that you thought you were all right at but need to work on a lot.
"I'll never be where I want to be as a player. Luckily in training I get to test myself against other very good scrum halves so your standards can never drop.''
England will be watching closely when Georgia face Scotland tomorrow but they are already acutely aware of what to expect.
Argentina bossed England at the breakdown and Youngs insisted they cannot afford to be second best in the physical exchanges to Georgia.
"They've got some very good players and very big men and they'll look to dominate us physically,'' said Youngs.
"After watching the Argentina game they'll probably go hard at our breakdown. We've addressed that and been harsh on ourselves.''
Gilbert has released a new line of rugby cleats. The Gilbert Virtuo 8S is part of the exciting new product. Check it out.
The entire All Blacks apparel line has been updated for 2013/14. Check out the New Zealand All Blacks polo.
The Nike Tiempo is a solid rugby cleat and one of few styles still made from full-grain natural leather.
The Gilbert Blitz 8S rugby cleat is a great cleat at a great price of $69.99. Get a new pair of cleats today.
A cool looking all black rugby cleat with the high performance adidas is known for. Get in the Gear!
Wear the crest of the British and Irish Lions on your t-shirt. A great look for the summer.
The All Blacks Performance t-shirt is black with hints of blue from the training jersey. Very Cool.
The New Zealand All Blacks training jersey for 2013/14. Get in the Gear!
The USA Rugby Pro Alternate rugby jersey is perfect for any fan of the Eagles. Get yours to wear during the summer Test matches.
The NEW All Blacks 2013/14 jersey has arrived at World Rugby Shop. Dare to wear the colors of the All Blacks.