We stayed this February in Torremolinos, we stayed for 4 nights and had a lovely time.
We had warm weather, tshirts during the day and a jacket at night. I wouldn`t say it was busy but there were enough bars open, the ones we went in had a few people in, busy enough without being overcrowded.
Have a fab time, it`s luck of the draw on the weather but bound to be better than at home.
If the weather is not so good have a train ride into Malaga, take the sightseeing bus around the city, you can hope on and off at the different stops.
Torremolinos has some lovely shops and tapas bars.
Go to Gibraltar for the day.
The list is endless.