I was lifting weights and my arm gave out and now i got a pain in my arm 2 weeks later?

i was sidelined for a few weeks when i returned to lift i did my whole work out fine only when i addedmore weights for my final bench press (dum bells) and my right arm just sort of gave out i had to awkwardly manuver my arm in a funny position so i wouldnt get smacked in the face and now i have this pain in my arm its fine for like a few minutes i can lift things and whatever and out of no where bam i get this pain in my arm what should i do why is it there what can be done or is it one of those time will heal if so how long ibeen taking a break from lifting not wanting to injure it more any ideas? thanks (weird how it will work fine now pain nothing i can lift and normal than a sharp pain 2 weeks later?