I felt truly dreadful coming off it too, was on 75mg (venlaxafine retard) too. It's a very low dose and I honestly don;t know how people on a higher dose mange to get off it. It's famously hard to stop.
Had the same symptoms as Impractical, also brain-zaps, dizziness, feeling very trippy, general weakness, impaired cognition. All round crap.
You say you're reducing the dose slowly, but how slowly? Being more than 12 hours late taking a dose was enough to give me withdrawal symptoms, I found. That's pretty common with venlaxafine. Have they had you halve your dose in one jump, by any chance?
My GP gave me an (allegedly) slow reduction schedule. A half dose 2 days a week and full dose one the other days to start off with, IIRC. It was dreadful, not manageable and left me unable to function properly. Was worse than the sudden halving of the dose, I think. That didn't go well either mind.
Anyway, there were various attempts to stop and none worked.
So, in the end, with her approval, I reduced my dose by extending the time between doses, in steps, giving the symptoms time to settle (5-6-7 days, I forget). It took a bit of calculating and it really was slow but I meant I was able to stop the stuff without the withdrawal symptoms messing with my mental health. Which was nice.
I was on the slow release stuff so the lowest dose available is a 37.5mg capsule. THe non-slow release stuff is available in liquid form which means a truly slow reduction in dose without all the faffing with time is easier. The withdrawals from that one are harder than from the slow release though, from what I've heard.
Waffle.
But, in any case. How bad do you feel? Is it manageable? TBH it's pretty certain to be with withdrawls rather than you. It's very hard work coming off this stuff. Day 3 after a reduction used to be the worst for me, if I remember right. Was uphill from there on in.
So. I'd say, if the withdrawls are manageable for you ATM and it's a stable daily dose (37.5mg per day?) then it'd probably be best to stick at that dose until your withdrawals are gone and the Work Thing is sorted. Then look at maybe finding a 'softer' way to reduce further.
But. If they're having you take different doses on different days or the withdrawals you're having aren't manageable then it may well be best to go back up to the original dose and start a different reduction plan later.