Having a hard time getting my head around the correlation...

Having a hard time getting my head around the correlation between live coin prices eg at ccn.com and what happens in my coinspot buy/sell/wallet.

I am really not confident i am getting the current rate when i trade... or there are no fingers going into my wallet.

Case in point last night there was a big drop on 3 coins i trade, i picked the bottom nicely, booked what i calculated would be around 7% profit, ended up with less than i started with... the total trades cost was like $60 i should have made about $300 on top of that... instead balance was back to evens after selling.

I do run my sell trades to USDT instead of converting to AUD as that attracts a 3% fee (wtf). Selling to USDT and back is 1%.

Watching the USDT price it sits evenly close to parity with USD with a 1% either way, but i leave my wallet (all in USDT) for 2 hours this morning, come back and have lost %10 of balance... ? USDT shows a mild gain of like 0.5%

I check the AUD/USD that's not swinging wildly as far as I can tell ..?

Wtf