Your inner critic is basically self-sabotage in the form of that little voice in the back of your head telling you to pull up the horses while beating you about the head with the full gambit of bullshit reasons around why you're not worthy, and suggesting all sorts of compromises that you should make on your dreams.
It tells you not to put yourself out there and how whatever you're into will never ever work. In fact, it will pretty much tell you anything to stop you living life on your own terms.
I've got more used to the ongoing dance with my inner critic in recent years. I've also noticed there seems to be a direct correlation between both the frequency & severity of attack and how important something I'm doing is to me and how close I am to actually doing or achieving that something. That's to say, be prepared that when you're about to or are actually making progress on what that lights you up (in a good way), this is when you're quite possibly most at risk of encountering an all-guns blazing shit show from yours.
Don't worry though - don't let that stop you - it's actually a sign you're doing good! I reckon anyway; it means we're trying for something significant.
Thankfully too, because this ain't my first rodeo and having gone innumerable rounds with mine at this point and starting to pay a bit more attention instead of just writing myself off as hopeless - well now I can see it for what it really is - a compulsive liar & absolutely full of crap. I've learned a few tricks too that work well for me in putting my inner critic firmly back in it's box when it rears up. Perhaps you'll find them helpful too...
Steps for quashing a vicious inner critic attack:
1 Start paying attention to the signs so over time you can learn to recognise it for what it is when it arises. i.e. if you start going into one doubting or trash talking yourself, or find yourself striking a downgrade bargain from what it is you really want, or utilising any other form of self-flagellation really... then HELLO! That useless **** is back. It takes PRACTICE, so don't be disheartened if it takes a while to start identifying when you're under attack. Sometimes you're too distracted by it to be able to be an outsider observer if you know what I mean. Even if it's a day or two later the penny drops, you deserve a pat on the back from yourself that you did. Keep at it and the recognition time will shorten, it will.
2 When in the midst of an attack, no matter what you're feeling or what your inner critic is bashing you about with, please try your hardest to be kind to and gentle with yourself. If you can't do anything else at the time but take to your bed and cry into Gilmore Girls re-runs, that's ok - but try to LOVE ON YOU while you're doing it.
3 Remind yourself that THIS TOO SHALL PASS. It sounds totally corny I know, but it's true, and it works for me.
4 FEEL WHAT YOU'RE FEELING and NAME IT if you are able, e.g. "I am fucking rip-roaring raging" - "I feel really unloved and unwanted" - "I'm afraid" - "I'm scared I don't belong anywhere" - whatever it might be. It's just you getting to know & being honest with you; no one else needs to know if you don't want them too.
5 What small things can you do to let even a small shimmer of light in? e.g. write in your journal, play uplifting music, dance around the lounge in your PJs with your baby on your hip, lash out your essential oils, read some positive stuff (even scanning the uplifting memes on Insta works for me now quite a lot, LOL!), phone a trusted friend, exercise, get arty, cook, take a bath, go on a spontaneous adventure with your kids or have an impromptu midnight snack of peanut butter on toast & tea. It's amazing how sometimes the simplest things can get you out of your head (where you're inner critic mainly plays) and into your body or your heart to shake things up a bit.
I hope this was helpful in some way, and I'd love to know if you have other strategies that work well for you.