3.5 hours isn't too bad. I have not been sending bitcoin lately so I don't know the transaction time but in 2017 It took a week and one took over a week. It worried me but I knew it would eventually go through or reject which is very annoying since you lose your fees. You can't really trade with bitcoins it takes much too slow and costs far too much. Better to use other currencies with next to no fee. Just hodl your bitcoins for now I think.