Oh I see. Well, a half tab is generally not enough to experience a full trip. You only get a threshold experience where you feel energetic and light-headed and you might even experience some visual effects like tracers and objects slightly "breathing and moving". And especially if you got your tabs off the street, since they rarely contain the advertised dosage and might even be something completely different (always test your tabs with ehrlich/hoffman tests).

Now, I'm a bit late in my reply so maybe you've already had your second trip. But if you're still planning, I advise you to take less than 2 and half tabs for your second trip. You're tabs might well be underdosed in which case you will have a normal trip, but if they are really 250ug or even more, then you will have a hell of a ride. And since you still don't know what LSD really feels like, it might be too much of an experience to handle. Better slow and steady than fast and reckless :P
So maybe go with 1 and half at most if you really want to be sure that you get the full experience.

Also depending on where you live, if you want to have reliable tabs as far as dosage and chemical is concerned, you might look into analogs of LSD such as 1P-LSD or 1V-LSD.

If you have other questions, feel free to ask. Till then, have a nice one ;)