Hi Helena, I'm a physio. Gary actually invited me to comment.. Tendinopathies don't like compression, rest of being stretched initially..so unless you're rolling your hamstring muscle belly, I'd let it be. If it's the insertion on your sit.bone that you're feeling it, prolonged sitting can be quite aggravating, especially on hard surfaces.. The best management is to work within your initial pain free movement and actively try to strengthen your hamstrings. If you not sure how to go about doing that, I suggest going to visit a Physio with an interest in running. Passive management like massage and stretching will only get you so far, strength is your friend..
@Helena Martin that sounds good. The nordics maybe a little aggressive initially. I usually only busy them out when insertion symptoms have settled. The scar tissue will breakdown under load, so get stuck into the exercises. Jammies Han be annoying, but consistent strength work will get you there.