Investing carries a degree of risk, but as you mentioned, you should have guidance. Even though some coins are currently worth more than others, you should still learn about them before you start investing because you can start investing without knowing anything about them. Moreover, you can learn how to hold your Bitcoin and use the little money you currently have to make better investments later on.
Because you can acquire bitcoin now and be concerned about selling it later that month, anyone who does so will not make a profit, and it will still be a loss because you can identify your capital and talkless of claim the gain. If you wish to invest in Bitcoin, only invest money that you can afford to lose.