No, its Slavic, the wars and borders have changed a lot over the years so there has been some cross breeding with Germanic people.
Correct, genetic analysis has shown that people in northwestern Poland have an unusually high frequency of the I1 Y-DNA haplogroup which is common in Germanic territories such as northern Germany, Denmark, Sweden, and other areas. This data clearly shows the Germanic heritage of some Poles. Western Poland in general also has a relatively high frequency of the R1b haplogroup which can suggest additional Celtic/Germanic ancestry.
As far as the language goes, Polish is obviously a Slavic language but it does share some words with the German language. For example, the word kino which means theater in both Polish and German.