Hi Fiona,
Yes, it can (subdrop for those who don’t know is feeling down or depressed after an intense bdsm experience – usually best fixed with cuddles, chat and biscuits – see more here).
Denial can definitely make things more intense and messes with your endorphin and adrenaline responses somewhat so they aren’t what you’re used to.
However, in my experiences this is pretty temporary and you soon adjust emotionally and physically to being denied and things get pretty much back to normal, although perhaps with a bit more of an impact than before.
However for some it lessons it as you don’t get the big hormone spikes that come with orgasm, so it can even serve to level things off!
Stick with it, see how it effects you a few more times, and most of all just be communicating with your dom to make sure they are being more vigilant in the aftercare you need while you both figure out the effects and if it’s for you.
Hope that helps
James