Achey breaky shins

Hi everyone I'm looking for a bit of advice about my shins please. I've done a search on here but there's such a myriad of posts on shin splints, shin pain etc that I'm now a bit confused :-S and tbh I don't even know what a shin splint is. What I do know is that when I did some shuffling on the treadmill this morning my shins felt sore. I don't think that they were painful as such, they just felt like the muscles were a bit tight, like you would expect them to feel the day after a hard workout, if that makes sense? I've only been to the gym once last week and twice this week so I don't think that I'm over-training. The only thing I can think of is that maybe my first 1 minute stint was a bit fast? As soon as I slowed down and started walking it out they felt fine. I eased up on the speed for the other 4x 1 minute stints and they seemed to be better. I haven't had any problems with them all day but when I just took my dog for a walk, I tried a 10 second jog and they felt a bit sore then too. Can anyone give me some advice please? I don't want ruin it before I even start!! Many thanks Rosie