Scared and confused

I’m currently 18 weeks pregnant and I’ve been with my fiancé for almost 3 years. We supposed to get married after we have the baby. Now I’m not sure. He left his phone downstairs and I used it to call my mom then just so happened to check his snap. I don’t know what I was looking for but something told me to check it. I found these. Should I be worried? He never said that he dated this girl before.

For a little context about the rent. After a year of being together he had to move out of his current place and I let him stay with me until he could find somewhere else (he never left). I was in college still and I was working. He got laid off. I paid for him that whole year. I paid rent, food, and gas money. He said when we move into this next place I will just have to pay utilities so I can get my money back. Also I pay for all of the animals. He doesn’t spend a dime on them. I just feel so betrayed. My heart is beating so fast and I can’t breathe. I’m so upset. I feel stuck. I’m currently not working because of covid. I helped him pay for a lot of stuff so I’m currently in debt. With no where to go. I’m scared.