First be really sure it is a DDOS, a lot of people come here complaining of that when it is something different.
A vpn does you no good if you can not change the actual ip address of you home connection. If you change the ip and then always use vpn you can not be DDOS because nobody can get you actual ip.
Your router should be full of log messages if you are actually getting DDOS. You should see massive numbers of session sending huge amount of data from multiple remote ip addresses. If you only see a couple it is not DDOS everyone gets some scans and they hurt nothing if there are not a not huge number every second.