Rat Big Enough?

[OSMDEATHOWNER]

So my Female BP Ice is about 3 years old and 3feet, 4inches long. I switched her to F/T Small Rats from live. After the first f/t feed she had, which she ate two small Rats, I switched her to medium F/T Rats. I think this is a good size for her but after the tail is also swallowed and her jaw is readjusted, she doesnt have a budge and after like 1 minute, she doesnt even look like she just ate a rat. I dont wanna feed her nothing too big so im asking for opinions. Should I just keep her at Medium for a while, or consider a bigger meal. This is her third medium Rat feed.