only 2 full days in thailand.. what to do?

hey all! i'm going to thailand for the first time in a few weeks for a work trip and have a few days at the end of my trip for a short bit of sightseeing before i have to go home. here's whats planned of my trip so far:

i fly into bangkok and then am going straight to pattaya.
i'm working in pattaya and should finish work around 5pm on those days.
i have 2 full days completely free, and then leave the next day out of bangkok at around midday.

i'm trying to decide where to spend my two full free days. my initial instinct is to just go to bangkok and spend my free days there but would be open to seeing any other nearby areas if it was feasible.

a few questions about my itinerary:

• what is the best way to get from BKK to pattaya? i'll be arriving at BKK in the evening
• what will i have time to do or see after work in pattaya?
• how should i spend my 2 full days? where should i go?
• what area would you recommend to stay in bangkok?

thanks so much in advance for your help all, and i apologise if any of these questions seem straightforward! i've never travelled to thailand before and don't know many people who have either