Hello and thank you for using just answer.
Adding any additives such as SurSeal is a very very very bad idea, my fear with this is that you have coated and CONTAMINATED the system and thus locked up what was a good compressor.
First the freeon level does need to be checked to be sure that this is not as simple as a low (or overcharged) system locking out compressor engagement. Also keep in mind that if you have a leak and are adding freeon then this means that you are not only losing freeon but also OIL in the system, it is also likely in this situation that the system was low on oil and has locked the compressor.
Yes this should be addressed by a professional. Another note on the 2003 corolla is that the Relay for the compressor is known to freeze internally, be sure that the compressor is recieving power from the realy here.

The compressor is powered by the relay. If the freeon level is to high or low then power is cut, so that is why I say check freeon level.
The a/c magnetic clutch relay is in the fuse block under the hood behind the battery, switch the relay for the a/c with the HORN relay for a few minutes to be sure that this is not a simple relay issue.

That is whatneeds to be determined, open the fuse block cover under the hood where I described earlier, there is a map for fuse and relay locations on the inside of the cover, switch these 2 relays and tell me if the horn still works and if the compressor now works, tell me what you find.