I found it hard initially, because French sentence structure and word order isn't easy to a native English speaker. So I left German alone for a while, until French became easier. Then doing both at the same time wasn't an issue
Learning one language is hard but worth it. Learning two at the same time is harder. I suggest that you favor one and remain on each beginning lesson for the other for days until you feel up to the challenge.
They are different languages and they don't belong to the same family, if you are already used to the German language I don't think that learning French will be a problem but you have to stay consistent and maintain both languages everyday.
It depends what kind of learner you are. If you don't mind doing lots of things at a time, you should do both. But if you like to take things slowly and one at a time, stick with your French and then come back to German. What do you think will work best for YOU?
No, probably not, although you may find one language easier than the other. I did both from junior high through college. Once you get a bit farther in German, you could try doing French through German (laddering), which will improve both languages.