If you want to be sure you get the full effects from your dose (best if you still have to figure out how much is enough or too much with a certain drug), a week is minimal and 2 weeks or more even better.
However if you have a relatively mild trip, there may be less tolerance development and it is possible to trip again with less time waited. I recently did AL-LAD (LSD-like drug) about 5 days after I took a 2 gram mushroom trip which is not that much more than half a full dose. Effects were limited with the mushrooms as expected, however it is certainly possible the effects from AL-LAD were also diminished. I took a dose of that which was plenty, I would have been okay with stronger effects but it was my first time with it. Since I have a lot of tripping experience in general I was prepared to handle a pretty wide range of effects. With less experience it is better to try and be more precise about the dose and effects to achieve since it can be challenging enough to begin with (pun not really intended).
With that in mind, doses can be increased to compensate but you should be really careful with that with limited experience! Not in the least because tolerance can be unpredictable. I am not sure what factors are involved with the rate at which receptor downregulation (the biological effect that is related to tolerance) is reversed. Like I said earlier milder trips may logically cause less downregulation since the reaction of your body can be expected to be more or less proportionate. But milder psychedelics may also elicit weaker reaction and less tolerance.
That is not relevant with LSD and mushrooms since those are the complete package: classic psychedelics with a full-on full-width range effect profile.
Good luck and safe tripping.
p. s. edit: Oh yeah almost forgot: Ismene already hints to it - psychedelia (psychedelic effects) is typically quite disappointing if you don't wait long enough. I personally believe it can work like a quota whether a trip is satisfactory / worthwhile: after a good and worthwhile trip IMO you have little chance of achieving it again extremely soon after, but after a trip with limited result it can be surprisingly good if you try again. Still, only if you wait like 4-5 days and the attempt at trying to find a dosage sweet spot is experienced / educated / sophisticated.
</sarcasm>
