I'm another noob and lover... And I need some help :)

[I~=Spam]

I think what you would do it set all globals to zero and call love.load. If you wrote your code well (put all loading things in love.load) it should work. But there is a better way. Just use gamestates. Link here: https://github.com/kikito/stateful.lua It is a library written by kikito (he writes lots of awesome libs centered around LOVE check out his github account for all of his stuff https://github.com/kikito).

For having multiple levels maybe you could use gamestates. Here is a great example game that kikito wrote: https://github.com/kikito/ekrixion