Manchester United are not panicking. Okay, so it might look like they are, but they're definitely not. After all, if they were panicking, presumably they'd have heard Borussia Dortmund say "Marco Reus will cost you £60m" and said something like "yes, yes, please, take our money, take it all."
That is what didn't happen when United, partway through negotiating Adnan Januzaj's loan to the German league leaders, brought up the possibility of taking Reus the other way. According to ESPN FC:
Dortmund were not totally resistant to the sale, and quoted United a price of £60m to begin discussions, but the Old Trafford club were only willing to go as far as £50m.
You might think that sounds like a decent basis for some negotiation, but apparently not.
In other news, the fee for Anthony Martial was apparently "upped ... by £15m because they knew that United were eager to add a forward". Apparently the sight of a United squad containing only Wayne Rooney is provoking amusement and opportunism across Europe.
Manchester United are definitely not panicking.