There is nothing to regret in investing your wanted crypto in a low value because that will be the right time and opportunity to buy some more coins because the true believer of crypto knows that even we are experiencing a long period of dipping down there will be a possible rising up that is soon to come so there is really nothing to be worry. No one can blame you in what your made decision maybe your being nervous and afraid to risk that time so my advice to you is just try to risk or invest but not all that you have because you need also to secure your investment so just invest what you are applicable to give. But to be sure there will we a next time and by that time don't be hesitate just go for the risk.