Buying in batches is the best option to solve these situations.
We cannot overcome panic and greed. But we should develop strategies and implement them before trading. This allows us to not panic when placing orders.
If you really can't adapt to this state, market trading is not for you. They are cruel, and most people will lose money for a reason.
That's known also as a dollar cost averaging. Which is one of the best strategies out there that can be tried by anyone. So if you're unsure whether you've bought at the dip, that will be the solution for you to keep yourself with the market as you buy and do DCA. Overcoming panic and greed is possible and that can happen when you're no longer that the same person that tackles it and you know how to flee from it already because of your experience as a trader. But newbies can't at the beginning.