When you create spells, measure them against other spells to determine the appropriate level. Spell level is tied more to the spell’s complexity than to the apparent power. A spell that causes a small wind by telekinetically moving air will be very low level. A spell that causes a small wind by opening numerous tiny holes to another dimension will be very high level (and will probably cause problems with the Space/Time Continuum).
Spells that transfer mass or energy between times, time-lines, or universes are likely to create vortices or warps in the Space/Time Continuum. Spells that transfer mass, energy, or spirits between the astral planes are likely to do the same to the Astral Continuum.