Nice shots but in both of them you're struggling with the focus/DoF.
#1 has an aperture of f3.2 which doesn't give you much depth of field. Combined with your shutter speed at 80 anything you shoot will have to be very precise, close together and motionless.
#2 has the same problem with even narrower depth of field at F2.8 and an even slower shutter speed of 0.6 seconds.
I see from the surroundings that you were struggling to shoot in low light without flash. I know the situation. However, both were shot at an ISO of 400. Your Rebel T5 has (I think) the capability of going to ISO 12,800. Yes, you'll get noise at higher ISO but noisy is better than OoF!
Play around with shooting at higher ISO in low light situations and get to know what your results will be.
You can also get free Depth of Field calculators for smart phones which may help you work your DoF margins out before you shoot.
Excellent points by Granddad; in addition to that, I would suggest going with strobed lighting rather than relying on ambient. Two inexpensive speedlights could have turned this from "almost" to "Damn!"
In addition to eliminating the need for high ISO, large aperture and low shutter-speed, in the first image a speedlight close in camera right would have eliminated the rather harsh and unattractive specular highlights on Batman's left shoulder. A second light, camera left would have allowed for the addition of some much-needed fill. In the second, it would have allowed sufficient DoF to have the seen in focus and much more attractive and dramatic highlights.
I agree with your feedback, both of you , thank you for taking the time to critique my images.
I didn't wish to choose a higher iso but mind you I will consider that next time. A second speed lite on the left side of batman would have been great. I only used one speed lite at the right side of them, with an umbrella. I am purchasing a second speed lite soon enough at least! I should have used a higher f-stop agreed, but hey trial and error.
But better luck next time I guess!
You've got an eye for a good shot Amanda and IMHO that's more important than having £20,000 worth of kit and knowing all the theory. As my signature line says "It's not brain surgery, it's photography; if you make a mistake nobody dies. Try again!"
On ISO; you have to balance the light triangle somewhere. If your camera will do higher ISO why not use it? I shot a show in London the weekend before last and I was using ISO 2500 or higher most of the time, I needed the shutter speed to be able to capture dance and my good lens (the one with good auto-focus) on zoom is only F5.6.
P.S. If budget is an issue consider the Yongnuo speedlights. I was so pleased with mine (and the price) that I got a 2nd one.