Zebra stripes

I haven't loaded my game in about a month. I updated and started to play. I bought two potions. One cost 4,000 and the other 1,000 .Neither showed up in my inventory. I restarted the game completely,still nothing. On the second reload,I went to travel & while at the select a destination,my screen started to show big black stripes going in a constant loop,I was able to save and exist,but everything was blurry and glitchy. I thought it was my Mac at first,then I tabbed out to check and nothing was happening to my actual computer screen. I'm not sure if anyone else had had either of these issues, it sucks to think my game is unplayable.