Calf problem

Hi everyone, I know there is a lot on calf injures but I would appreciate it if anyone can help with my problem. It all started last July when I was training for a half marathon. At the start of my runs my calf would feel tight but not so much as I had to stop running, but once I got into my run it would be fine and there would be no pain....until I stopped. I would hobble around and not be able to walk properly. I tried taking a week/two weeks off and then go back running. I would be fine for my first run but the next time I would go out it would return. During my training I went on holiday to Spain and even went on a little run while there. On holiday my calf was fine, no issues at all. Even after me coming back I had no problems what so ever with it during training. In November I join a local athletics club and still had no problems until after Christmas. Over the Christmas period there was two weeks where I just chilled and ate loads of turkey. On coming back to training my calf problems have returned and two weeks ago I had to pull out of training after warm up because my calf was feeling like it was cramped and tight. But when I was running the part of my calf that I get the pain in felt loose and when I stopped went tight again. I am stretching properly before running and training and just don't understand why the problem has returned. Does anyone know what it could be or anything to try solve it? I would go back to Spain to fix I again but can't quite afford another holiday.