Can I return a bike (the day after purchasing) and ask for a full refund? (Fråga)

Yesterday evening I bought a 2nd hand bicycle in a Swedish shop. After paying for it I realise that it wasn’t working properly because the handlebars of front part was very short. I ask him, and he told me to come back the following day (today) around 3pm in order to fix it. So, I returned home by bike. In the way back home I realise that the breaks were not working as expected. So, I would like to return the bike and buy another one. Can I request him a full refund? does he have to give me back my money?

Thank you in advance.