<human>: I'm a casual runner. I've done 5ks every day of the week before, and also spent months away from running. This last week I got back after an absence and started with 4mi. The next day my left ankle had a dull throb, but I went for 2mi anyway because I assumed I was just sore and it felt better for a time. It's been a week now and this dull throbbing has become an ever present  sharp throbbing even when I spend 9 hours a day in an office chair. 

There's no visible swelling or bruising, it just fucking hurts. I'd rate it a 3/10 or something. I can ignore it but it's always there. 

Worth noting I have a weird swelling on my upper left calf that has been there for years. It's about the size of a dime, and becomes much more visible after a run. I've no idea if it's related but assume not as its been years.

Can you give me the gist of the text in a nutshell?
<bot>: my left ankle hurts. It's been a week. How long should I wait and assume it's a sprain before checking with a medical expert?