Alko Tow Hitch problem (or not!)

Morning. Although not new to towing, I am new to towing a caravan with an Alko Hitch. Just bought a 2008 Swift Challenger. First tow it has become apparent that when pulling away from a roundabout ot traffic lights, there is a ‘lag’ from the caravan whilst I presume the hitch fully extends out, followed by a ‘thud’ as it reaches its end of range. Is this normal, or a sign that something is not right? Off the car, the hitches resistance to being pushed in, by hand, is comparable to others I have tried, but its return to the extended position is painfully slower than others and it does not make it fully out. Am I being concerned about something or nothing? Thanks in advance