6 month old vomiting

So last night my baby ate a chunk out of a valentines card. Around 6:00 pm. Then around midnight she woke up and threw up, the chunk of paper came up. Everything else was normal for the rest of the night and morning. At 9:30 this morning I gave her some avacado, she probably didn’t even eat an ounce. She then nurses for about 50 min about 30 min after the avacado. Then at noon she threw up. She threw up again about 20 min later, but not near as much. Since then she has been spitting up/gagging about every 30 min. What could e causing this? She seems fine in between...no fever or any other symptoms. Could the avacado have looked fine but actually have been bad? Or could the paper have something to do with it?

***she has had avacado several times before so I wouldn’t think she is allergic

*** the paper was all thrown back up last night