Stalling Problems/Exhaust

My car had a hole in the exhaust, and I brought it to get it fixed. They "fixed it" the day before Christmas, and on christmas day I drove 70 miles to my families house, on the way there, it was clear that their job didn't work and the car was very loud. On the way back, the car began bucking and we couldn't drive faster than 40 miles on the highway. We drove it like this for approximately 40 miles so we could get it back to the shop. They said that their welder was broken and sent us to another shop. The other shop fixed it, and then this week (a month to the day later), the exhaust fell apart again. This week it stalled twice, but we thought nothing of it. We brought it back to the shop, and they said that the welder was STILL broken, but they would do their best. When we left, the car seemed fine, but then began stalling at every stoplight or stop sign. (Basically any time I come to a stop). It stalled 19 times yesterday.

Is it possible that the problem with my car stalling is directly related to the strain it endured while I was driving with the exhaust falling apart? (I didn't have time to get the shop for 2 days after it fell apart the most recent time. I had classes from 925 to 5 and they closed at 6pm).