Extremely low download speed - seeking help and advise

hi there,
i am hoping someone with more experience can give me some advise. since two
days now i have been experiencing an incredible slow download speed. it
actually took me about 23 hours to download a simple epsidoe (350mb) and that
is just unacceptable. usually it takes me maximum 4 hours, some times even
only an hour. the download and upload speed that i was observing was extremely
slow for both cases and i am not sure if this is due to the fault with my
broadband or because of something else. the internet othewise was doing fine,
but opening a website is of course something different than downloading an
episode.
can someone give me some advise on this?

need more information

including

client
adsl line speed
port forwarding or upnp
tracker prob exp on
and anything else u can muster
dht on/off

etc etc etc

maybe your provider uses traffic shaping (just a guess) to decrease your
bittorrent speed specifically. at some german universities this is used as an
alternative to just blocking ports. seems to be more effective even though they
are technically not blocking bittorrent, right?

if your bittorrent speed stays this low and normal downloads using your browser
stay fast, this might be the case.

i will have a look as you suggested. i do not quite know all the details...i
am not the most technical person there is.
i have bittorrent client
dsl line
broadband/wireless
not sure about the others...
and it is not only the download that is slow also the internet connection in
general...it is still working, but you can tell that it is a bit slow on side.
hopefully it will go away by itself...thank you for trying to help and
anything else you can think off, please let me know.