Defender Collins rightly concedes Villa should have effectively put the tie beyond Blackburn's reach with the chances they created in the opening 55 minutes, with referee Mark Clattenburg most notably dismissing claims for a clear-cut penalty that instead saw striker Gabriel Agbonlahor booked for simulation.
Martin O'Neill's side were almost made to pay for their profligacy as Blackburn came close to an equaliser around the hour mark with striker Nikola Kalinic twice hitting the right-hand post, initially with a header and then a left-foot shot.
Villa survived and with the second leg on home soil next Wednesday, the midlands outfit are firmly in the driving seat and on course to face either Manchester United or Manchester City in the final at Wembley at the end of February.
"We should have put it beyond their reach before they had their chances," reflected Collins.
"The penalty shout was clear-cut but didn't go our way, so we're a bit aggrieved - but then they've hit the post twice, so it all equals out.
"We've won 1-0, which is a good result and we are happy to take that to Villa Park, and now we're looking forward to the second leg.
"We are halfway through the semi-final and we are 1-0 up taking them to our place, so it's a massive chance.
"There are a lot of boys who have not been to Wembley and it's a massive incentive. If we play the way we played in the first half there is no reason why we can't finish off the job."
Although Collins has now started and played in Villa's last two matches, both cup wins over Blackburn, he appreciates he may be back on the bench for Sunday's Premier League visit of former club West Ham.
Following his £5million move from Upton Park in the summer, Collins formed a formidable partnership with Richard Dunne at the heart of Villa's defence until the Welshman sustained a groin injury in a 2-1 defeat at the Hammers in early November.
After recovering from the injury, Collins found his return to the first team blocked by Carlos Cuellar, since when he has been forced to bide his time - with O'Neill using the cup encounters to help the 28-year-old regain his fitness.
"I'm still trying to get back to full fitness, but the game last night played a big part and now I'm in the team I will be looking to stay there," insisted Collins.
"The injury was obviously frustrating. I had a few when I was at West Ham. I seem to get on a run of games then pull up with an injury.
"Luckily this time it wasn't as bad as what I've had previously and I was back in a couple of weeks, and now I'm looking to get back into the form I was in before the injury.
"But this squad is so hard to break into. It's superb. Carlos came across from right-back and played centre-half and did so well, with Luke Young then excellent at right-back.
"It's happened to a few of the boys where they've been injured then dropped. I'm just here to take my chances and play as many games as I can. "