Stress with managing toddler behavioural issues

Hi mums and dads,

I'm in a bind with my 17 mo and I feel like a rotten mum.
I grew up with some emotional and physical trauma as a child and teen and am worried my manner may be affecting my little one.

My girl plays up a lot with me where she laughs when I try to firmly correct and discipline her.
I have tried smacking on the bottom or the hand but I actually don't want to repeat history, so I avoid it.
So I've found myself raising my voice. Not screaming (as I have a pet hate of this in women) but trying to speak in a firm tone. I think with her hearing me speak this way to the pets, she's immune to it now.

Some days she won't sleep when I especially need her to (where her sleep is mostly one a day if I'm lucky).

When I pop her down for her day sleep (morning or arvo) she treats it like it's fun. She knows to shut her eyes but jumps back up and plays in her cot and throws her bed toys and dummies out (I usually leave 2 of each).
I've told her if she doesn't "go to sleepy", mummy will take her dummy away.
Well I resorted to that and she screamed blue murder. It's not a first but it doesn't seem to make a difference. I end up going back in and telling her why mummy did this and give it back... then the whole thing repeats.
I don't think i have handled that well AT ALL.
This also applies to her throwing her toys at the dogs or even at us.

Saying "no" or "ah ah" and briefly explaining why just doesn't seem enough, and only creates this screaming toddler when I remove her from the play area.

One of her behaviours also involves her rolling her eyes back and smacking her face or rolling her eyes and smearing some food on her face/head.
It's odd behaviour that I haven't seen before. And to be honest it scares the "sh$t" out of me but what's interesting is that she's such a bright,
engaging, cheery and observant little girl most of the time.
So I wonder if this is only a response particularly when she's over tired.

My concern is this may happen more often because she fights the sleep some days and whether it rolls into a regular thing. I think this is where I need to curb my own first to make sure I'm not part of the problem.

I actually don't know what is "normal" toddler behaviour compared to "concerning" behaviour. And how to respond.

I know there will be mixed views and I don't want people to view me as a bad mum even though I feel this way.
I feel like I've traumatised her and don't want to impact her that way whatsoever considering I was a very emotional little girl, and cried a lot.
I don't think I've set a good precedent for her really. Is my history repeating?
I'm trying to prevent that from becoming her pattern of responses as she grows. To be honest I'm really scared about this.

I have also noticed she sometimes moans in her sleep and worry that she may be doing this as a reflection of me being so firm. Whether she dreams these experiences. I remember as a young child having very stressful dreams with a firm female voice that must have traumatised me. It wasn't my mum because she was always so gentle and kind. It's strange and thinking about I feel very strange.

So the last thing I want is to create nightmares for her. Who knows how their little minds react and process.

Sorry this is so long winded. I'm at my wits end and need some constructive and kind parenting advice and suggestions.

I'd love and appreciate some references of affordable courses to help me, even courses about understanding toddlers and how to appropriately respond, and recognise signs before things escalate.

I found a parenting resource page in NSW that provides very affordable face to face courses yet nothing like this in Victoria.
We're a single income family which is part of the problem as I find online courses provide some of what I need although prefer to attend face to face courses to speak to other parents/facilitators where possible.

Also I don't want my girl to be assessed at this stage if the issue is more with me as opposed to her. If that makes sense. And if i changed something in my management then it might change everything.

Thanks again. I'm feeling so unsettled about all this.