Alternatives to Excel to store experimental data
This answer is assuming you are either interested in or already experienced in entry-level programming.

For the programming language Python, a data structure package called Pandas exists. To use it, you can utilize basic python syntax which is not that hard to learn. 

There is also extensive documentation and online help on SE forums available. When coming from Excel, you might want to check out this tutorial.

Disclaimer: I have not used it to a great extent, since I did not have any applications for it, but a coworker of mine uses it on a regular basis, and has grown very fond of it despite not having any previous programming experience.