The 23-year-old helped Villa to priceless victories over Reading and QPR over the last two weeks before joining up with the Republic squad for their World Cup qualifiers against Sweden and Austria.
Clark is now intent on playing his part in a successful fight against relegation, and he also hopes to establish himself as a regular starter in Giovanni Trapattoni's Republic side.
On Villa's relegation dogfight, he said: "The last two weeks, we have had some good results. It's always nice to come away after having two good results like that.
"It would have been a lot tougher if we had come away knowing we had lost two games. It's always a big confidence boost when you have won two games like that.
"The belief has always been there with us, it's just been about getting the results and hopefully we can start to pick up now.
"From 10th place to the bottom, it's still very tight. With seven or eight games to go, there are a lot of things that can happen still and a lot of teams that can get sucked into it."
The Republic of Ireland face a tough trip to Sweden on Friday before hosting Austria in Dublin four days later, and Clark is keen to prove his worth to Trapattoni.
Asked if he felt he had done enough to warrant selection, he said: "I would like to think so.
"You can only do what's been asked. To get the clean sheet was obviously good for us in the last game, and especially to get the win.
"But no matter who plays, they will go out and they will give it their best and hopefully we will do enough to get the three points."