Points assigned to issues are representative of either the amount of time or the amount of effort you expect to put in fixing them. Usually, the lower the number, the lesser the effort/expected time to be spent on a ticket.

During sprint planning (the meetings where you’re supposed to have those numbers assigned), ask questions about the tickets. If you’re not sure about the amount of work it’d take, try to get more clarity before committing to it or assigning points. Talk to your PO, Business Analyst and/or Scrum Master.

And if you don’t have the bandwidth to take on an extra ticket at the moment, try to gauge its priority. If it can be delayed to the following sprint, ask your scrum master to keep it in the backlog until then if it can’t be delayed, reassess the priorities of the stories you currently have assigned to you.

If you have older devs on your team, get their insights as well on the tickets. They can give you a fairly accurate estimate of what it’d take to complete the work, and assist you as needed.

Depending on the project and how laid back folks are, you can get away with carrying over stories.

If you feel like a sprint was too heavy in terms of workload, reassess things, discuss that during the retrospective meeting at the end of the sprint, or directly with the team’s leaders and try to do a better job estimating things moving forward.

Good luck.