You may have done what is called a 'backflash' of the sample into cooler parts of the injector. Once deposited there, repeated injections of solvent may 'wash' them out onto the column and to the detector.
OR
You may have a lot of active sites in your injection port or on the column itself and deposited your analyte on them. Then additional injections of solvent may dislodge them and allow them to elute to the detector.
Knowledge of the appropriate injection liner, the amount of sample to be injected, and the speed of sample injection and evaporation are not always present among those teaching you how to do GC.
Of course there is the oldest error of all, not washing your syringe and having traces of the previous sample when you take up the next injection solution.
Good luck,
Rodney George