It is not possible to answer your question. Even religions tethered by a written text, an organized clergy, and rigid dogma can be fluid, changing from time to time and practiced differently in diverse places. Pre-conversion Scandinavia did not have a written text, an organized body of spiritual leaders, or rigid dogma, so that belief system was particularly susceptible to fluidity. What little evidence that exists about beliefs about the afterlife come from texts written by Christians generations after conversion. These rare references may or may not be accurate when it comes to pre-conversion beliefs, but whatever they are by way of accuracy, they cannot hope to reflect the entire spectrum of possibilities. What one person might have believed happened to anyone who died - in battle, after battle, or dying of old age - is not necessarily what another might believe, particularly when considering the vast geography and expanse of time to be considered during the pre-conversion period.

In short, there was no dogma during that time, and so there is no definitive answer to your type of question.

In addition to /u/itsallfolklore's helpful answer, you might like these older post which is a bit longer and gets into other aspects of your question:

If a viking was wounded in battle but then died after it from infection or similar, did they believe that they would still go to valhalla? by /u/bloodswan