Joglusker

As of yesterday I’ve been having a pretty strange issue with the headlights on my s4. Pop ups work perfectly, but only the driver’s side light works on low beams. Now here’s where it gets cool. When I flash the high beams, the drivers side turns off and passenger high beams go on. I can’t imagine the bulbs are blown because they worked perfectly fine before I had to let the car sit for 2 months due to corona. Any help appreciated!

Bonus question: I’m looking to pressure test my coolant system for leaks, where can I find an adapter radiator cap for a pump?