PLT EXPERIENCED RWY INCURSION AT SAT.

Narrative

I AM A DESIGNATED PLT EXAMINER AND I HAD FINISHED CONDUCTING A CHK RIDE ON THE NE SIDE OF SAT. I HAD ADDITIONAL BUSINESS ON THE OTHER SIDE OF THE ARPT AND WAS REPOSITIONING MY AIRPLANE TO AN FBO UNDER GND CTL ON FREQ 121.9. I HEARD THE CTLR SAY SOMETHING LIKE 'TAXI VIA TXWYS R AND D AND HOLD SHORT OF RWY 30L.' THIS INSTRUCTION WOULD ALLOW ME TO CROSS RWY 30R WITHOUT FURTHER COMMENT; HOWEVER IT IS MY PRACTICE TO ALWAYS ANNOUNCE WHEN I AM XING AN ACTIVE RWY; AND I DID THIS. (ACFT X IS XING RWY 30R.) WHEN I SAID THIS THE CTLR SAID NO! AND BASICALLY CHEWED ME OUT IN A RAISED EMOTIONAL VOICE; TELLING ME THAT I WAS NOT CLRED TO CROSS THE RWY AND HAD BEEN TOLD TO HOLD SHORT OF RWY 30R. I HAD NOT YET CROSSED RWY 30R AND VERY CONFUSED; I HELD SHORT OF THE RWY. I THEN HEARD THE CTLR TELL ME TO CROSS RWY 30L. I TAXIED ACROSS RWY 30R AND AS I WAS XING RWY 30L THE CTLR SAID 'ACFT X WHAT ARE YOU DOING?' I EXPLAINED THAT I WAS UNDER THE IMPRESSION THAT HE HAD INSTRUCTED ME TO CROSS BOTH RWYS; HE SAID 'NO; NO; NO; CALL THE TWR HERE IS THE PHONE NUMBER.' I BELIEVE WHAT MAY HAVE HAPPENED IS THAT DUE TO THE RECENT RWY CHANGE; THE CTLR MAY HAVE MISTAKENLY REFERRED TO RWY 30R AS RWY 30L IN THE ORIGINAL INSTRUCTION. AFTER THAT I HAVE NO IDEA WHO MADE THE MISTAKE. IT COULD HAVE BEEN ME BECAUSE I WAS UPSET AT BEING YELLED AT ON FREQ. A MORE IN CTL CTLR MIGHT HAVE MERELY RE-INSTRUCTED ME TO HOLD SHORT OF RWY 30R; WAIT FOR THINGS TO COOL DOWN; AND THEN RE-INSTRUCT ME.